Phenylcarboxamide beta-secretase inhibitors for the treatment of Alzheimer&#39;s disease

ABSTRACT

Disclosed are compounds of formula (I) 
                         
which are inhibitors of the beta-secretase enzyme and that are useful in the treatment or prevention of diseases in which the beta-secretase enzyme is involved, such as Alzheimer&#39;s disease and pharmaceutical compositions comprising these compounds and the use of these compounds and compositions in the prevention or treatment of such diseases in which the beta-secretase enzyme is involved.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Phase application under 35 U.S.C. §371 of PCT Application No. PCT/US03/353 16, filed Nov. 6, 2003, whichclaims priority under 35 U.S.C. § 119(e) from U.S. ProvisionalApplication Ser. Nos. 60/425,555, filed Nov. 12, 2002 and 60/425,560,filed Nov. 12, 2002.

FIELD OF THE INVENTION

The present invention relates to phenylcarboxamide compounds that areuseful for the prevention and treatment of Alzheimer's disease. Moreparticularly, the present phenylcarboxamide compounds are usefulinhibitors of β-secretase, the β-site amyloid precursor protein-cleavingenzyme (“BACE”).

BACKGROUND OF THE INVENTION

Alzheimer's disease is characterized by the abnormal deposition ofamyloid in the brain in the form of extra-cellular plaques andintra-cellular neurofibrillary tangles. The rate of amyloid accumulationis a combination of the rates of formation, aggregation and egress fromthe brain. It is generally accepted that the main constituent of amyloidplaques is the 4 kD amyloid protein (βA4, also referred to as Aβ,β-protein and βAP) which is a proteolytic product of a precursor proteinof much larger size. The amyloid precursor protein (APP or AβPP) has areceptor-like structure with a large ectodomain, a membrane spanningregion and a short cytoplasmic tail. The Aβ domain encompasses parts ofboth extra-cellular and transmembrane domains of APP, thus its releaseimplies the existence of two distinct proteolytic events to generate itsNH₂- and COOH-termini. At least two secretory mechanisms exist whichrelease APP from the membrane and generate soluble, COOH-truncated formsof APP (APP_(s)). Proteases that release APP and its fragments from themembrane are termed “secretases.” Most APP_(s) is released by a putativeα-secretase which cleaves within the Aβ protein to release α-APP_(s) andprecludes the release of intact Aβ. A minor portion of APP_(s) isreleased by a β-secretase (“β-secretase”), which cleaves near theNH₂-terminus of APP and produces COOH-terminal fragments (CTFs) whichcontain the whole Aβ domain.

Thus, the activity of β-secretase or β-site amyloid precursorprotein-cleaving enzyme (“BACE”) leads to the abnormal cleavage of APP,production Aβ, and accumulation of β amyloid plaques in the brain, whichis characteristic of Alzheimer's disease (see R. N. Rosenberg, Arch.Neurol., vol. 59, September 2002, pp. 1367–1368; H. Fukumoto et al,Arch. Neurol., vol. 59, September 2002, pp. 1381–1389; J. T. Huse et al,J. Biol. Chem., vol 277, No. 18, issue of May 3, 2002, pp. 16278–16284;K. C. Chen and W. J. Howe, Biochem. Biophys. Res. Comm, vol. 292, pp702–708, 2002). Therefore, therapeutic agents that can inhibitβ-secretase or BACE may be useful for the treatment of Alzheimer'sdisease.

The compounds of the present invention are useful for treatingAlzheimer's disease by inhibiting the activity of the β-secretase orBACE, thus preventing the formation of insoluble Aβ and arresting theproduction of Aβ.

SUMMARY OF THE INVENTION

The present invention is directed to compounds that are inhibitors ofthe β-secretase enzyme that are useful in the treatment or prevention ofdiseases in which the β-secretase enzyme is involved, such asAlzheimer's disease. The invention is also directed to pharmaceuticalcompositions comprising these compounds and the use of these compoundsand compositions in the prevention or treatment of such diseases inwhich the β-secretase enzyme is involved.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to compounds of the formula I:

wherein:

-   R¹ is selected from the group consisting of:

-   R² is selected from the group consisting of:    -   (1) R⁴—S(O)_(m)—NR⁵—,    -   (2) R⁴—S(O)_(m)—,    -   (3) R⁴NHCO—,    -   (4) R⁴CONH—,    -   (5) R⁴R⁵N—,    -   (6) nitrile,    -   (7) NC—C₁₋₆alkyl-,    -   (8) halogen,    -   (9)

-   R³ is selected from the group consisting of:

-   R⁴ is selected from the group consisting of:    -   (1) hydrogen,    -   (2) C₁₋₆alkyl,    -   (3) phenyl, and    -   (4) benzyl;-   R⁵ is independently selected from the group consisting of:    -   (1) hydrogen,    -   (2) C₁₋₆alkyl,    -   (3) phenyl, and    -   (4) benzyl;-   R^(6a), R^(6b), and R^(6c) are independently selected from the group    consisting of:    -   (1) hydrogen,    -   (2) halogen,    -   (3) —OR⁵,    -   (4) —SR⁵, and    -   (5) C₁₋₆alkyl;-   R⁷ is selected from the group consisting of —C═C—, O, S, and NH;-   Z is selected from the group consisting of CO, CH—OH, CH—F and

-   R^(8a) and R_(8b) are independently selected from the group    consisting of:    -   (1) nitrile    -   (2) hydrogen,    -   (3) halogen,    -   (4) —OR⁵,    -   (5) —SR⁵,    -   (6) C₁₋₆alkyl,    -   (7) —CO₂R₅, and    -   (8) tetrazolyl;-   X¹ is hydrogen and X² is hydroxyl, or X¹ and X² together form oxo;-   n is independently 1, 2, 3, or 4;-   m is independently 0, 1, or 2;-   and pharmaceutically acceptable salts thereof.

An embodiment of the present invention includes compounds of the formulaIA wherein X¹ and X² of formula I together form oxo:

Another embodiment of the present invention includes compounds of theformula IB wherein X¹ of formula I is hydrogen and X² of formula I ishydroxyl:

An embodiment of the present invention includes compounds of the formulaI wherein R¹ is:

and wherein n is 2 or 3, R⁵ is hydrogen or methyl, and pharmaceuticallyacceptable salts thereof.

Another embodiment of the present invention includes compounds of theformula I wherein R¹ is:

and wherein n is 1, and pharmaceutically acceptable salts thereof.

Another embodiment of the present invention includes compounds of theformula I wherein R¹ is:

and wherein R⁵ is hydrogen or methyl and Z is selected from the groupconsisting of CO, CH—OH, and

and pharmaceutically acceptable salts thereof.

Another embodiment of the present invention includes compounds of theformula I wherein R² is:R⁴—S(O)₂—NR⁵—and wherein R⁴ is selected from the group consisting of:

-   -   (1) hydrogen,    -   (2) C₁₋₆alkyl,    -   (3) phenyl, and    -   (4) benzyl;

-   R⁵ is selected from the group consisting of:    -   (1) C₁₋₆alkyl,    -   (2) phenyl,    -   (3) benzyl, and    -   (4) hydrogen;        and pharmaceutically acceptable salts thereof.

Another embodiment of the present invention includes compounds of theformula I wherein R³ is:

and wherein R⁴ is methyl, R^(6a) is H or F, R^(6b) and R^(6c) arehydrogen, and pharmaceutically acceptable salts thereof.

Another embodiment of the present invention includes compounds of theformula I wherein R³ is:

and wherein R⁵ is methyl, R⁷ is O or NH, and pharmaceutically acceptablesalts thereof.

Another embodiment of the present invention includes a compound offormula IA which is selected from the group consisting of:

Another embodiment of the present invention includes a compound offormula IB which is selected from the group consisting of:

and pharmaceutically acceptable salts thereof.

Several documents disclose compounds that may be relevant to thephenylcarboxamide compounds of the present invention, for exampleWO99/61423 (Derwent 2000-097099), WO99/54305 (Derwent 2000-052697),WO99/54320 (Derwent 2000-023164), WO99/54310 (Derwent 2000-023162),DE19818614 (Derwent 2000–000334), DE19817461 (Derwent 1999-591908),WO98/25883 (Derwent 98-348419), DE19650975 (Derwent 98-323649),WO95/12611 Derwent 95-185737), WO96/22275, WO02/002505, US 2002/0128255and US 2002/0016320.

The compounds of the instant invention have at least one asymmetriccenter. Additional asymmetric centers may be present depending upon thenature of the various substituents on the molecule. Compounds withasymmetric centers give rise to enantiomers (optical isomers),diastereomers (configurational isomers) or both, and it is intended thatall of the possible enantiomers and diastereomers in mixtures and aspure or partially purified compounds are included within the scope ofthis invention. The present invention is meant to encompass all suchisomeric forms of these compounds.

The independent syntheses of the enantiomerically or diastereomericallyenriched compounds, or their chromatographic separations, may beachieved as known in the art by appropriate modification of themethodology disclosed herein. Their absolute stereochemistry may bedetermined by the x-ray crystallography of crystalline products orcrystalline intermediates that are derivatized, if necessary, with areagent containing an asymmetric center of known absolute configuration.

If desired, racemic mixtures of the compounds may be separated so thatthe individual enantiomers are isolated. The separation can be carriedout by methods well known in the art, such as the coupling of a racemicmixture of compounds to an enantiomerically pure compound to form adiastereomeric mixture, followed by separation of the individualdiastereomers by standard methods, such as fractional crystallization orchromatography. The coupling reaction is often the formation of saltsusing an enantiomerically pure acid or base. The diasteromericderivatives may then be converted to the pure enantiomers by cleavage ofthe added chiral residue. The racemic mixture of the compounds can alsobe separated directly by chromatographic methods utilizing chiralstationary phases, which methods are well known in the art.

Alternatively, any enantiomer of a compound may be obtained bystereoselective synthesis using optically pure starting materials orreagents of known configuration by methods well known in the art.

The compounds of the present invention are prepared by the methodsoutlined in Schemes 1A–1C and 2.

Referring to Scheme 1A, N,N-dibenzyl-L-phenylalanal (II) is obtained byoxidation of the corresponding alcohol (I), and is reacted with anN-Boc-protected cyclic amine in the presence of an alkyl lithium reagentto afford a mixture of protected amine alcohols (III). The N-Bocprotected alcohol (III) is debenzylated by catalytic hydrogenation, andcoupled to an appropriate benzoic acid (IV) in the presence of BOPreagent and base, to obtain the protected amide V.

In Scheme IB, the amide (V) is oxidized with the Dess-Martin reagent anddeprotected with TFA to provide the final product (VII), to obtaincompounds of formula IA.

In Scheme 1C, the amide V is deprotected with TFA to provide the finalproduct VIII, to obtain compounds of formula IB.

A wide variety of N-Boc-protected cyclic amines are applicable to thisScheme, and include examples where the cyclic amine is aziridine,azetidine, pyrrolidine, piperidine, or the like, and also encompassesexamples with substitution on other ring carbons, provided that suchsubstitution is inert to the lithiation conditions required in the nextstep, and allows for a slightly acidic hydrogen adjacent to thenitrogen. Examples of such substitution are alkyl groups, protectedalcohols, protected ketones such as ketals or ketone equivalents.

A wide variety of benzoic acids (IV) are applicable to Scheme 1, andinclude examples where R² is sulfonamide, sulfone, amide, amine,nitrile, alkylnitrile, halogen, phenyl, and cyanocycloalkyl. R³ of thebenzoic acid in Scheme 1 is generally selected from a carboxyaminobenzylgroup, a substituted olefin, an O- or N-alkyl cyclopropyl, or an alkylether, alkylthioether, or secondary alkylamine.

Referring to Scheme 2, an appropriate benzoic acid derivative (IV) iscoupled to an appropriate primary amine in the presence of BOP reagentand base to provide an amide (X). This substance is N-protected,oxidized with Dess-Martin reagent, and deprotected to afford the finalproducts (XIII).

A wide variety of benzoic acids are applicable to Scheme 2, and includeexamples where R² is sulfonamide, sulfone, amide, amine, nitrile,alkylnitrile, halogen, phenyl, cyanocylcoalkyl. R³ of the benzoic acidin Scheme 2 is generally selected from a carboxyaminobenzyl group, asubstituted olefin or an O- or N-alkyl cyclopropyl, or an alkyl ether,alkylthioether, or secondary alkylamine.

In the hydroxyethylamine reactant (IX) of Scheme 2, the R groups arepreferably cycloalkanes.

The term “substantially pure” means that the isolated material is atleast 90% pure, and preferably 95% pure, and even more preferably 99%pure as assayed by analytical techniques known in the art. The term“substantially enantiomerically pure form” means that at least 90%(preferably 95%, and more preferably 99%) of a compound is present inthe form of a single enantiomer. The term “substantiallydiastereomerically pure form” means that at least 90% (preferably 95%,and more preferably 99%) of the referenced compound is present in theform of a single diastereomer.

The term “pharmaceutically acceptable salts” refers to salts preparedfrom pharmaceutically acceptable non-toxic bases or acids includinginorganic or organic bases and inorganic or organic acids. Salts derivedfrom inorganic bases include aluminum, ammonium, calcium, copper,ferric, ferrous, lithium, magnesium, manganic salts, manganous,potassium, sodium, zinc, and the like. Particularly preferred are theammonium, calcium, magnesium, potassium, and sodium salts. Salts in thesolid form may exist in more than one crystal structure, and may also bein the form of hydrates. Salts derived from pharmaceutically acceptableorganic non-toxic bases include salts of primary, secondary, andtertiary amines, substituted amines including naturally occurringsubstituted amines, cyclic amines, and basic ion exchange resins, suchas arginine, betaine, caffeine, choline, N,N′-dibenzylethylene-diamine,diethylamine, 2-diethylaminoethanol, 2-dimethylaminoethanol,ethanolamine, ethylenediamine, N-ethyl-morpholine, N-ethylpiperidine,glucamine, glucosamine, histidine, hydrabamine, isopropylamine, lysine,methylglucamine, morpholine, piperazine, piperidine, polyamine resins,procaine, purines, theobromine, triethylamine, trimethylamine,tripropylamine, tromethamine, and the like.

When the compound of the present invention is basic, salts may beprepared from pharmaceutically acceptable non-toxic acids, includinginorganic and organic acids. Such acids include acetic, benzenesulfonic,benzoic, camphorsulfonic, citric, ethanesulfonic, fumaric, gluconic,glutamic, hydrobromic, hydrochloric, isethionic, lactic, maleic, malic,mandelic, methanesulfonic, mucic, nitric, pamoic, pantothenic,phosphoric, succinic, sulfuric, tartaric, p-toluenesulfonic acid, andthe like. Particularly preferred are citric, hydrobromic, hydrochloric,maleic, phosphoric, sulfuric, fumaric, and tartaric acids.

Utility

The present invention is directed to the use of the compounds disclosedherein as inhibitors of β-secretase enzyme activity or β-site amyloidprecursor protein-cleaving enzyme (“BACE”) activity, in a patient orsubject such as a mammal in need of such inhibition, comprising theadministration of an effective amount of the compound. The terms“β-secretase enzyme,” “β-site amyloid precursor protein-cleavingenzyme,” and “BACE” are used interchangeably in this specification. Inaddition to humans, a variety of other mammals can be treated accordingto the method of the present invention.

The present invention is further directed to a method for themanufacture of a medicament or a composition for inhibiting β-secretaseenzyme activity in humans and animals comprising combining a compound ofthe present invention with a pharmaceutical carrier or diluent.

The compounds of the present invention have utility in treating,preventing, ameliorating, controlling or reducing the risk ofAlzheimer's disease, other diseases mediated by abnormal cleavage ofamyloid precursor protein (also referred to as APP), and otherconditions that may be treated or prevented by inhibition ofβ-secretase. Such conditions include mild cognitive impairment, Trisomy21 (Down Syndrome), cerebral amyloid angiopathy, degenerative dementia,Hereditary Cerebral Hemorrhage with Amyloidosis of the Dutch-Type(HCHWA-D), Creutzfeld-Jakob disease, prion disorders, amyotrophiclateral sclerosis, progressive supranuclear palsy, head trauma, stroke,Down syndrome, pancreatitis, inclusion body myositis, other peripheralamyloidoses, diabetes and atherosclerosis.

The subject or patient to whom the compounds of the present invention isadministered is generally a human being, male or female, in whominhibition of β-secretase enzyme activity is desired, but may alsoencompass other mammals, such as dogs, cats, mice, rats, cattle, horses,sheep, rabbits, monkeys, chimpanzees or other apes or primates, forwhich inhibition of β-secretase enzyme activity or treatment of theabove noted disorders is desired.

The compounds of the present invention may be used in combination withone or more other drugs in the treatment, prevention, control,amelioration, or reduction of risk of diseases or conditions for whichthe compounds of the present invention have utility, where thecombination of the drugs together are safer or more effective thaneither drug alone. Additionally, the compounds of the present inventionmay be used in combination with one or more other drugs that treat,prevent, control, ameliorate, or reduce the risk of side effects ortoxicity of the compounds of the present invention. Such other drugs maybe administered, by a route and in an amount commonly used therefor,contemporaneously or sequentially with the compounds of the presentinvention. Accordingly, the pharmaceutical compositions of the presentinvention include those that contain one or more other activeingredients, in addition to the compounds of the present invention. Thecombinations may be administered as part of a unit dosage formcombination product, or as a kit or treatment protocol wherein one ormore additional drugs are administered in separate dosage forms as partof a treatment regimen.

Examples of combinations of the compounds of the present invention withother drugs in either unit dose or kit form include combinations with:anti-Alzheimer's agents, other beta-secretase inhibitors,gamma-secretase inhibitors, IMG-CoA reductase inhibitors, NSAID'sincluding ibuprofen, N-methyl-D-aspartate (NMDA) receptor antagonists,such as memantine, cholinesterase inhibitors such as galantamine,rivastigmine, donepezil, and tacrine, vitamin E, CB-1 receptorantagonists or CB-1 receptor inverse agonists, antibiotics such asdoxycycline and rifampin, anti-amyloid antibodies, or other drugs thataffect receptors or enzymes that either increase the efficacy, safety,convenience, or reduce unwanted side effects or toxicity of thecompounds of the present invention. The foregoing list of combinationsis illustrative only and not intended to be limiting in any way.

Compositions

The term “composition” as used herein is intended to encompass a productcomprising specified ingredients in predetermined amounts orproportions, as well as any product which results, directly orindirectly, from combination of the specified ingredients in thespecified amounts. This term in relation to pharmaceutical compositionsis intended to encompass a product comprising one or more activeingredients, and an optional carrier comprising inert ingredients, aswell as any product which results, directly or indirectly, fromcombination, complexation or aggregation of any two or more of theingredients, or from dissociation of one or more of the ingredients, orfrom other types of reactions or interactions of one or more of theingredients. In general, pharmaceutical compositions are prepared byuniformly and intimately bringing the active ingredient into associationwith a liquid carrier or a finely divided solid carrier or both, andthen, if necessary, shaping the product into the desired formulation. Inthe pharmaceutical composition the active object compound is included inan amount sufficient to produce the desired effect upon the process orcondition of diseases. Accordingly, the pharmaceutical compositions ofthe present invention encompass any composition made by admixing acompound of the present invention and a pharmaceutically acceptablecarrier.

Pharmaceutical compositions intended for oral use may be preparedaccording to any method known to the art for the manufacture ofpharmaceutical compositions and such compositions may contain one ormore agents selected from the group consisting of sweetening agents,flavoring agents, coloring agents and preserving agents in order toprovide pharmaceutically elegant and palatable preparations. Tabletscontain the active ingredient in admixture with non-toxicpharmaceutically acceptable excipients which are suitable for themanufacture of tablets. The tablets may be uncoated or they may becoated by known techniques to delay disintegration and absorption in thegastrointestinal tract and thereby provide a sustained action over alonger period.

Compositions for oral use may also be presented as hard gelatin capsuleswherein the active ingredient is mixed with an inert solid diluent, oras soft gelatin capsules wherein the active ingredient is mixed withwater or an oil medium.

Aqueous suspensions contain the active materials in admixture withexcipients suitable for the manufacture of aqueous suspensions. Suchexcipients may be suspending agents or dispersing or wetting agents orthe like. The aqueous suspensions may also contain one or morepreservatives, coloring agents, flavoring agents, or sweetening agents.The compositions for oral use may also be prepared as oily suspensions,or in the form of oil-in-water emulsions, or as syrups or elixirs.

The pharmaceutical compositions may also be in the form of a sterileinjectable aqueous or oleagenous suspension, or may be prepared in theform of a suppository for rectal administration of the drug, a topicalformulation, an inhalant or as a transdermal patch, according to theknowledge of those skilled in the art or pharmaceutical formulations.

By “pharmaceutically acceptable” it is meant the carrier, diluent orexcipient must be compatible with the other ingredients of theformulation and not deleterious to the recipient thereof.

The terms “administration of” or “administering a” compound should beunderstood to mean providing a compound of the invention to theindividual in need of treatment in a form that can be introduced intothat individuals body in a therapeutically useful form andtherapeutically useful amount, including, but not limited to: oraldosage forms, such as tablets, capsules, syrups, suspensions, and thelike; injectable dosage forms, such as IV, IM, or IP, and the like;transdermal dosage forms, including creams, jellies, powders, orpatches; buccal dosage forms; inhalation powders, sprays, suspensions,and the like; and rectal suppositories.

The terms “therapeutically effective amount” means the amount of thesubject compound that will elicit the biological or medical response ofa tissue, system, animal or human that is being sought by theresearcher, veterinarian, medical doctor or other clinician. As usedherein, the term “treatment” refers both to the treatment and to theprevention or prophylactic therapy of the mentioned conditions,particularly in a patient who is predisposed to such disease ordisorder.

The compositions containing compounds of the present invention mayconveniently be presented in unit dosage form and may be prepared by anyof the methods well known in the art of pharmacy. The term “unit dosageform” is taken to mean a single dose wherein all active and inactiveingredients are combined in a suitable system, such that the patient orperson administering the drug to the patient can open a single containeror package with the entire dose contained therein, and does not have tomix any components together from two or more containers or packages.Typical examples of unit dosage forms are tablets or capsules for oraladministration, single dose vials for injection, or suppositories forrectal administration. This list of unit dosage forms is not intended tobe limiting in any way, but merely to represent typical examples in thepharmacy arts of unit dosage forms.

The compositions containing compounds of the present invention mayconveniently be presented as a kit, whereby two or more components,which may be active or inactive ingredients, carriers, diluents, and thelike, are provided with instructions for preparation of the actualdosage form by the patient or person administering the drug to thepatient. Such kits may be provided with all necessary materials andingredients contained therein, or they may contain instructions forusing or making materials or components that must be obtainedindependently by the patient or person administering the drug to thepatient.

When treating, preventing, controlling, ameliorating, or reducing therisk of Alzheimer's disease or other diseases for which compounds of thepresent invention are indicated, generally satisfactory results areobtained when the compounds of the present invention are administered ata daily dosage of from about 0.1 milligram to about 100 milligram perkilogram of animal body weight, preferably given as a single daily doseor in divided doses two to six times a day, or in sustained releaseform. The total daily dosage is from about 1.0 milligrams to about 2000milligrams, preferably from about 0.1 milligrams to about 20 milligramsper kilogram of body weight. In the case of a 70 kg adult human, thetotal daily dose will generally be from about 7 milligrams to about1,400 milligrams. This dosage regimen may be adjusted to provide theoptimal therapeutic response. The compounds may be administered on aregimen of 1 to 4 times per day, preferably once or twice per day.Exemplary unit dosage forms which may be useful for treatment include 10mg, 25 mg, 50 mg, 75 mg, 100 mg and 150 mg unit dosage forms.

It will be understood, however, that the specific dose level andfrequency of dosage for any particular patient may be varied and willdepend upon a variety of factors including the activity of the specificcompound employed, the metabolic stability and length of action of thatcompound, the age, body weight, general health, sex, diet, mode and timeof administration, rate of excretion, drug combination, the severity ofthe particular condition, and the host undergoing therapy.

Biological Activity

The utility of the compounds in accordance with the present invention asinhibitors of β-secretase enzyme activity may be demonstrated bymethodology known in the art. Enzyme inhibition is determined asfollows.

FRET Assay

A homogeneous end point fluorescence resonance energy transfer (FRET)assay is employed with the substrate([TAMRA-5-CO-EEISEVNLDAEF-NHQSY]QFRET), which is cleaved by BACE 1 torelease the fluorescence from TAMRA. The Km of the substrate is notdetermined due to the limit of solubility of the substrate. A typicalreaction contains approximately 30 nM enzyme, 1.25 μM of the substrate,and buffer (50 mM NaOAc, pH 4.5, 0.1 mg/ml BSA, 0.2% CHAPS, 15 mM EDTAand 1 mM deferoxamine) in a total reaction volume of 100 μl. Thereaction is proceeded for 30 min and the liberation of TAMRA fragment ismeasured in a 96-well plate LJL Analyst AD using an excitationwavelength of 530 nm and an emission wavelength of 580 nm. Under theseconditions, less than 10% of substrate is processed by BACE 1. Theenzyme used in these studies was soluble (transmembrane domain andcytoplasmic extension excluded) human protein produced in a baculovirusexpression system. To measure the inhibitory potency of compounds,solutions of inhibitor in DMSO (four concentrations of the inhibitorswere prepared: 1 mM, 100 μM, 10 μM, 1 μM) were included in the reactionsmixture (final DMSO concentration is 0.8%). All experiments wereconducted at room temperature using the standard reaction conditionsdescribed above. To determine the IC50 of the compound, competitiveequation V0/Vi=1+[I]/[IC50] were employed to predict the inhibitorypotency of the compounds. The errors in reproducing the dissociationconstants are typically less than two-fold.

HPLC assay

A homogeneous end point HPLC assay is employed with the substrate(coumarin-CO-REVNFEVEFR), which is cleaved by BACE 1 to release theN-terminal fragment attached with coumarin. The Km of the substrate isgreater than 100 μM and can not be determined due to the limit ofsolubility of the substrate. A typical reaction contains approximately 2nM enzyme, 1.0 μM of the substrate, and buffer (50 mM NaOAc, pH 4.5, 0.1mg/ml BSA, 0.2% CHAPS, 15 mM EDTA and 1 mM deferoxamine) in a totalreaction volume of 100 μL. The reaction is proceeded for 30 min and thereaction is stopped by the addition of 25 μL of 1 M Tris-HCl, pH 8.0.The resulting reaction mixture was loaded on the HPLC and the productwas separated from substrate with 5 min linear gradient. Under theseconditions, less than 10% of substrate is processed by BACE 1. Theenzyme used in these studies was soluble (transmembrane domain andcytoplasmic extension excluded) human protein produced in a baculovirusexpression system. To measure the inhibitory potency for compounds,solutions of inhibitor in DMSO (12 concentrations of the inhibitors wereprepared and the concentration rage was dependent on the potencypredicted by FRET) were included in the reaction mixture (final DMSOconcentration is 10%). All experiments were conducted at roomtemperature using the standard reaction conditions described above. Todetermine the IC50 of the compound, four parameters equation is employedfor curve fitting. The errors in reproducing the dissociation constantsare typically less than two-fold.

In particular, the compounds of the following examples had activity ininhibiting the beta-secretase enzyme in the aforementioned assay,generally with an IC₅₀ from about 1 nM to 1 μM. Such a result isindicative of the intrinsic activity of the compounds in use asinhibitors of beta-secretase enzyme activity.

Several methods for preparing the compounds of this invention areillustrated in the following Schemes and Examples. Starting materialsare made according to procedures known in the art or as illustratedherein. The following examples are provided so that the invention mightbe more fully understood. These examples are illustrative only andshould not be construed as limiting the invention in any way.

Intermediate I

Step A. To a stirred slurry of dimethyl 5-aminoisophthalate (5.0 g,23.90 mmol) in 100 mL CH₂Cl₂/pyridine (3:1) at 0° C. was addedmethanesulfonyl chloride (1.85 mL, 23.90 mmol). The resulting mixturewas stirred for 4 h at room temperature. The solvent was removed invacuo and ethylacetate (100 mL) was added resulting in precitateformation. The product was collected by filtration to give thesulfonamide as a white solid. ¹H NMR (DMSO_(d6)) δ 8.15 (s, 1H), 8.02(s, 2H), 3.89 (s, 6H), 3.02 (s, 3H) LCMS [M-OCH₃]⁺=256.16.

Step B. To a solution of sodium hydride (0.153 g, 3.83 mmol, 60% oildispersion) in 10 mL DMF was added sulfonamide (1.0 g, 3.48 mmol) fromstep A followed by methyl iodide (0.43 mL, 6.97 mmol). After 1 hr thereaction was quenched with H₂O (100 mL) and extracted with EtOAc (3×50mL). The organic extracts were dried over MgSO₄ and evaporated to givethe product. ¹H NMR (DMSO_(d6)) δ 8.40 (s, 1H), 8.19 (s, 2H), 3.91 (s,6H), 3.34 (s, 3H), 3.01 (s, 3H). LCMS [M+H]=302.15.

Step C. Diester (1.03 g, 3.38 mmol) from step B was dissolved in 50 mLTHF:MeOH (1:1) and cooled to 0° C. 1N NaOH (3.38 mL, 3.38 mmol) wasadded and the reaction was allowed to warm to RT over 8 hours. Thesolution was acidified with 1N HCl (30 mL) and extracted with EtOAc(3×50 mL). The combined organic extracts were washed with brine anddried over MgSO₄, filtered and concentrated in vacuo. Purification onsilica gel (5% MeOH/CHCl₃ containing 1% HOAc) gave the mono acid. ¹H NMR(DMSO_(d6)) δ 8.30 (s, 1H), 8.10 (s, 2H), 3.84 (s, 3H), 3.27 (s, 3H),2.94 (s, 3H). LCMS (M+H)=288.16.

Step D. A solution containing 0.133 g (0.46 mmol) of the monoacid fromstep C in 5 mL CH₂Cl₂, BOP reagent (0.235 g, 0.55 mmol),(R)-(+)-α-methylbenzylamine (0.071 mL, 0.55 mmol), and diisopropylamine(0.24 mL, 1.39 mmol) was stirred at ambient temperature for 1 h.Evaporation of the solvent and column chromatography on silica gel (90%EtOAc/Hexanes) afforded the benzyl amide. ¹H NMR (CDCl₃) δ 8.26 (s, 1H),8.17 (s, 1H), 8.06 (s, 1H), 7.31 (m, 5H), 6.50 (d, J=7.1 Hz, 1H), 5.33(q, J=7.1 Hz, 1H), 3.96 (s, 3H), 3.37 (s, 3H), 2.88 (s, 3H), 1.64 (d,J=7.0 Hz, 3H). LCMS (M+B)=391.20.

Step E. To 0.171 g (0.438 mmol) of the benzyl amide from step D in 10 mLTHF:MeOH (1:1) was added 2 N NaOH (0.66 mL, 1.32 mmol). The solution washeated to 50° C. for 1 h. After cooling the solution was acidified bythe addition of 1 N HCl (20 mL) and extracted with EtOAc (3×30 mL). Thecombined organic extractions were dried over MgSO₄, filtered, andconcentrated in vacuo to yield the desired carboxylic acid. ¹H NMR(CDCl₃) δ 8.22 (t, 1H), 8.11 (m, 1H), 8.06 (m, 1H), 7.34 (m, 5H), 6.47(d, J=7.1 Hz, 1H), 5.33 (m, 1H), 3.37 (s, 3H), 2.87 (s, 3H), 1.64 (d,J=7.0 Hz, 3H). LCMS (M+H)=377.2.

Intermediate II

This carboxylic acid was prepared in the same manner as in intermediateI but using (R)-4-fluoro-α-methylbenzyl amine as the amine in step D.

Intermediate III

Step A. A solution containing 2.63 g (10.0 mmol) oftert-butyl[S-(R*,R*)]-(−)-(1-oxiranyl-2-phenylethyl)-carbamate in 30 mLof i-PrOH was treated with 6 mL of cyclopropyl amine and heated at 50°C. in a sealed tube for 16 h. The reaction mixture was cooled andevaporated to give the amino alcohol as a white solid that was pure byHPLC and used without further purification. LCMS (M+Na)=239.0.

Step B. A 0° C. solution containing 3.0 g (13.9 mmol) of the Bocprotected amino alcohol from step A in 50 mL of 4:1 EtOAc/MeOH wassubjected to a slow stream of HCl gas for 15 minutes. After stirring for3 h, the solvents were removed by rotory evaporation and the resultingsolid was triturated with ether and filtered leaving the title compoundas a crystalline white solid. LCMS (M+1)=186.3.

Intermediate IV

Step A: To 3-amino-5-nitrobenzoic acid (3.60 g, 19.78 mmol) in 100 mLMeOH was added thionyl chloride (2.59 g, 21.76 mmol). The solution washeated to 65° C. for 12 h. Concentration in vacuo afforded the methylester hydrochloride salt. ¹H NMR (CD₃OD) δ 8.62 (s, 1H), 8.28 (s, 1H),8.19 (s, 1H), 3.99 (s, 3H).

Step B: To a solution of 3.53 g (18.0 mmol) amino ester from step A in100 mL CH₂Cl₂/pyridine (3:1) was added methanesulfonyl chloride (2.07 g,18.0 mmol). The reaction was stirred at ambient temperature for 1 hfollowed by evaporation of the solvent. The gummy residue was taken upin EtOAc (100 mL), acidified with 1N HCl (100 mL), and extracted withEtOAc (3×100 mL). The combined organic extracts were dried over MgSO₄,filtered, and concentrated in vacuo to provide the sulfonamide as anoff-white solid. ¹H NMR (CD₃OD) δ 8.46 (s, 1H), 8.30 (s, 1H), 8.18 (s,1H), 3.97 (s, 3H), 3.09 (s, 3H).

Step C: Sodium Hydride (0.26 g, 6.55 mmol, 60% oil dispersion) wassuspended in 10 mL DMF to which 1.5 g (5.45 mmol) of the sulfonamidefrom step B (in 10 mL DMF) was added followed by 0.93 g (6.55 mL) methyliodide. The solution was stirred at ambient temperature for 3 h. Thereaction was quenched with H₂O (250 mL), extracted with EtOAc (3×200mL), dried over MgSO₄, filtered and concentrated in vacuo. Purificationby silica gel chromatography provided the N-methyl sulfonamide. LCMS(M−H₂O)=272.2.

Step D. To a solution of the nitro sulfonamide (2.7 g, mmol) from step Cand 0.15 g of 10% Pd/C in 50 mL EtOH containing HOAc (2 mL) was stirredat room temperature under a balloon of hydrogen gas for 12 h. Themixture was filtered through a pad of Celite, concentrated, and purifiedon silica gel (100% EtOAc) to afford the desired aniline. ¹H NMR (CD₃OD)δ 7.29 (s, 1H), 7.26 (s, 1H), 6.95 (s, 1H), 3.87 (s, 3H), 3.27 (sm 3H),2.89 (s, 3H). LCMS (M+H)=258.2.

Intermediate V

Step A. To a stirred solution of dimethyl 5-hydroxyisophthalate (8.6 g,41.1 mmol) in 200 mL of acetone was added K₂CO₃ (5.7 g, 41.1 mmol) andtrans-crotyl bromide (5.5 g, 41.1 mmol). The resulting mixture wasstirred at reflux for 16 h. The solids were removed by filtration andthe filtrate was evaporated to near dryness. The resulting residue wasdissolved in 200 mL of ether and washed 3×20 mL of 1N HCl then brine.The organic extracts were dried over MgSO₄ and evaporated to give arylether A. ¹H NMR (CDCl₃) δ 8.25 (s, 1H), 7.75 (s, 2H), 5.93 (m, 1H), 5.77(m, 1H), 4.58 (d, J=2.2 Hz, 2H), 3.91 (s, 6H), 1.81 (d, J=2.2 Hz, 3H).LCMS (M+H)=265.24.

Step B. A 0° C. solution containing 9.4 g (35.6 mmol) of theisophthalate from step A in 300 mL of a 1:1 mixture of THF and MeOH wastreated with 35.6 mL (35.6 mmol) of 1N NaOH. The ice bath was allowed tostir to ambient temperature over 16 h. The reaction mixture wasconcentrated to ca. ⅛ volume before it was acidified with 25 mL of 3NHCl. The solids that precipitated were redissolved in 300 mL of EtOAcand washed with brine (2×25 mL). The organic extract was dried overMgSO₄ and evaporated to afford the desired carboxylic acid. ¹H NMR(CDCl₃) δ 8.37 (s, 1H), 7.82 (s, 2H), 5.93 (m, 1H), 5.77 (m, 1H), 4.58(d, J=2.2 Hz, 2H), 3.95 (s, 3H), 1.77 (d, J=2.2 Hz, 3H). LCMS(M+H)=252.18

Step C. To a solution containing 2.5 g (10.0 mmol) of carboxylic acidfrom step B in 100 mL of THF was added 1.78 g (11.0 mmol) of CDI. Theresulting solution was stirred for 1 h then treated with 741 mg (20.0mmol) of NaBH₄ dissolved in 5 mL of water. After an additional hour atrt the reaction mixture was diluted with 200 mL of ether and quenchedwith 25 mL of 1N HCl. The organic phase was separated and dried overMgSO₄. Column chromatograhy (1:1 EtOAc/Hexanes) afforded of benzylicalcohol C. ¹H NMR (CDCl₃) δ 7.68 (s, 1H), 7.44 (s, 1H), 7.11 (s, 1H),5.85 (m, 1H), 5.65 (m, 1H), 5.20 (s, 2H), 4.74 (d, J=6.0 Hz, 2H), 4.444(s, 2H), 3.82 (s, 3H), 1.71 (d, 3H). LCMS (M+H)=237.22

Step D. A 0° C. solution of 1.65 g (7.0 mmol) of the alcohol from step Cwas dissolved in 50 mL of DCM and treated with 2.0 g (7.7 mmol) oftriphenylphosphine then 2.6 g (7.7 mmol) of CBr₄. The reaction mixturewas stirred to rt over 16 h, concentrated and chromatographed (1:4EtOAc/Hexanes) to afford the benzylic bromide D. ¹H NMR (CDCl₃) 7.62 (s,1H), 7.44 (s, 1H), 7.11 (s, 1H), 5.85 (m, 1H), 5.65 (m, 1H), 4.50 (d,J=6.0 Hz, 2H), 4.46 (s, 2H), 3.90 (s, 3H), 1.71 (d, 3H). LCMS(M+H)=299.13

Step E. To a solution of the benzylic bromide (2.1 g, 7.0 mmol) fromstep D in 50 mL of MeCN was added 1.05 g of TMSCN then 1 M TBAF in THF(10.5 mL). The reaction mixture was stirred at room temperature for 15 hafter which the solvent was removed and the residue chromatographed oversilica gel (3:7 EtOAc/Hexanes) to afford the desired nitrile. ¹H NMR(CDCl₃) 7.62 (s, 1H), 7.58 (s, 1H), 7.07 (s, 1H), 5.85 (m, 1H), 5.65 (m,1H), 4.50 (d, J=6.0 Hz, 2H), 3.97 (s, 3H), 3.75 (s, 3H), 1.79 (d, 3H).LCMS (M−13)=233.1.

Step F. To a 0° C. solution of the compound from step E (1.27 g, 5.2mmol) in 0.5 mL of THF was added 1.2 g (5.2 mmol) of benzyltriethylammonium chloride, 1.3 mL (11.0 mmol) of 1,3-dibromopropane and10.0 mL (100.0 mmol) of 10.0 N NaOH. The ice bath was removed after 5min and the reaction mixture was stirred to rt over 20 h. The reactionwas acidified with 12 N HCl (10 mL) and extracted with EtOAc (3×50 mL).The organic phase was dried and concentrated to afford the crudecyclopentylnitrile. This material was redissolved in 15 mL of EtOAc andtreated with 45 mL of 0.5 M ethereal CH₂N₂. After 5 minutes, 64 mg (0.2mmol) of Pd(OAc)₂ was added to effect effervescence. The reaction wasstirred 1 h, filtered through Celite, concentrated and chromatographed(1:3 EtOAc/Hexane) to give the desired compound. ¹H NMR (CDCl₃) δ 7.62(s, 1H), 7.47 (s, 1H), 7.12 (s, 1H), 3.87 (s, 3H), 3.83 (m, 2H), 2.44(m, 2H), 2.15–1.94 (m, 6H), 1.79 (d, 3H) 0.97 (m, 2H0, 0.75 (m, 2H),0.55 (m, 2H), 0.41 (m, 2H).

Step H. To a stirred solution of the ester from step F (801 mg, 2.56mmol) in 20 mL THF/MeOH (1:1) was added 15% NaOH (2.2 mL, 8.0 mmol).After the reaction mixture was stirred at 45° C. for 2 h the solventswere evaporated and the residue was acidified with 3N HCl (4.0 mL, 12mmol). The solid was taken up in 75 mL of DCM and the organic phase waswashed with brine. The organic phase was dried and evaporated to yieldthe desired carboxylic acid as a white solid that was used withoutfurther purification.

Intermediate VI

Step A. To a stirred solution of dimethyl 5-hydroxyisophthalate (8.6 g,41.1 mmol) in 200 mL of acetone was added K₂CO₃ (5.7 g, 41.1 mmol) andtrans-crotyl bromide (5.5 g, 41.1 mmol). The resulting mixture wasstirred at reflux for 16 h. The solids were removed by filtration andthe filtrate was evaporated to near dryness. The resulting residue wasdissolved in 200 mL of ether and washed 3×20 mL of 1N HCl then brine.The organic extracts were dried over MgSO₄ and evaporated to give arylether VI-A. ¹H NMR (CDCl₃) δ 8.25 (s, 1H), 7.75 (s, 2H), 5.93 (m, 1H),5.77 (m, 1H), 4.58 (d, J=2.2 Hz, 2H), 3.91 (s, 6H), 1.81 (d, J=2.2 Hz,3H). LCMS (M+H)=265.24.

Step B. A 0° C. solution containing 9.4 g (35.6 mmol) of theisophthalate from step A in 300 mL of a 1:1 mixture of THF and MeOH wastreated with 35.6 mL (35.6 mmol) of 1N NaOH. The ice bath was allowed tostir to ambient temperature over 16 h. The reaction mixture wasconcentrated to ca. ⅛ volume before it was acidified with 25 mL of 3NHCl. The solids that precipitated were redissolved in 300 mL of EtOAcand washed with brine (2×25 mL). The organic extract was dried overMgSO₄ and evaporated to afford the desired carboxylic acid. ¹H NMR(CDCl₃) δ 8.37 (s, 1H), 7.82 (s, 2H), 5.93 (m, 1H), 5.77 (m, 1H), 4.58(d, J=2.2 Hz, 2H), 3.95 (s, 3H), 1.77 (d, J=2.2 Hz, 3H). LCMS(M+H)=252.18

Step C. To a 0° C. solution containing 4.0 g (16.0 mmol) of carboxylicacid VI-C in 80 mL of THF was added 4.2 mL (30.2 mmol) of Et₃N and 2.2mL (22.7 mmol) of ethyl chloroformate. The resulting slurry was stirredfor 1 h and treated with 2.46 g (37.8 mmol) of NaN₃ dissolved in 15 mLof water. After an additional hour at rt the reaction mixture wasdiluted with 50 mL of water and washed toluene (3×50 mL). The combinedorganic extracts were dried over MgSO₄ and refluxed over 16 h. Thereaction was cooled to rt and treated with 3.1 mL (30.2 mmol) of benzylalcohol and 4.2 mL (30.2 mL) of triethylamine. The reaction was refluxedfor 24 h, cooled and diluted with 100 mL of EtOAc and 35 mL of 10%citric acid. The organic extract was washed with water and brine thendried over MgSO₄. Column chromatograhy (2:3 EtOAc/Hexanes) afforded thecarbamate VI-C. ¹H NMR (CDCl₃) δ 7.38 (m, 8H), 6.85 (bs, 1H), 5.85 (m,1H), 5.65 (m, 1H), 5.20 (s, 21), 4.44 (d, J=6.0 Hz, 2H), 3.82 (s, 3H),1.71 (d, 3H). LCMS (M+H)=356.25

Step D. A solution of 3.56 g (10.0 mmol) of the aryl ether from step Cwas dissolved in 100 mL of EtOAc and treated with 50 mL (c.a. 0.5 M, 25mmol) of freshly prepared CH₂N₂. After stirring for 5 minutes, 112 mg(0.5 mmol) of Pd(OAc)₂ was added to effect vigorous release of N₂. Afteran additional 30 minutes, the brown slurry was evaporated andchromatographed (1:1 EtOAc/Hexanes) to the cyclopropylmethyl ether VI-D.¹H NMR (CDCl₃) δ 7.55 (s, 1H), 7.44 (m, 7H), 6.80 (bs, 1H), 5.23 (s,2H), 3.85 (s, 3H), 3.80 (m, 2H), 1.04 (d, 3H), 0.94 (m, 1H), 0.75 (m,1H), 0.47 (m, 1H), 0.38 (m, 1H). LCMS (M+H)=368.26

Step E. To a solution of the benzyl carbamate (3.6 g, 10.0 mmol) fromstep D and 1.5 g of 10% Pd/C in EtOAc (100 mL) was stirred at roomtemperature under a balloon of hydrogen gas for 5 h. The mixture wasfiltered through a pad of Celite, concentrated, and purified on silicagel (50% EtOAc/Hexanes) to afford the desired aniline. ¹H NMR (CDCl₃) δ6.99 (s, 2H), 6.40 (s, 1H), 3.85 (s, 3H), 3.75 (m, 2H), 1.77 (m, 1H),1.45 (m, 1H), 1.04 (d, 3H), 0.47 (m, 1H), 0.33 (m, 1H). LCMS(M+H)=236.2.

Step F. To a 0° C. solution of the aniline from step E (940 mg, 4.0mmol) in 30 mL of CH₂Cl₂ and 5 mL of pyridine was added methanesulfonylchloride (0.40 mL, 4.0 mmol). The resulting mixture was stirred at thistemperature for 2 h before being diluted with 100 mL of DCM. Thesolution was washed with 1N HCl (3×25 mL), water (2×25 mL), and brine(25 mL). The organic phase was dried and concentrated to affordsulfonamide VI-F that was used in the next step without furtherpurification. LCMS (M+H)=314.1

Step G. The sulfonamide from step F (1.25 g, 4:0 mmol) in DMF (20 mL)was treated with 95% sodium hydride (106 mg, 4.4 mmol) and excess methyliodide (3 mL). The resulting mixture was stirred at ambient temperaturefor 1 h and was diluted with 200 mL of ether. The solution was washedwith water (7×25 mL) and brine then dried over MgSO₄. Purification bysilica gel chromatography (2:3 EtOAc/Hexanes) afforded of the desiredmethylated sulfonamide. ¹H NMR (CDCl₃ w/0.05% DMSO-d₆) δ 7.65 (s, 1H),7.41 (s, 1H), 7.15 (s, 1H), 3.93 (s, 3H), 3.80 (t, 2H), 3.30 (s, 3H),2.87 (s, 3H), 1.11 (d, 3H), 0.88 (m, 1H), 0.55 (m, 1H), 0.37 (m, 1H).LCMS (M+1)=328.23

Step H. To a stirred solution of the ester from step G (625 mg, 2.0mmol) in 12 mL THF/MeOH (1:1) was added 15% NaOH (2.2 mL, 8.0 mmol).After the reaction mixture was stirred at 45° C. for 2 h the solventswere evaporated and the residue was acidified with 3N HCl (4.0 mL, 12mmol). The solid was taken up in 75 mL of DCM and the organic phase waswashed with brine. The organic phase was dried and evaporated to yieldof the desired carboxylic acid as a white solid. ¹H NMR (CDCl₃ w/0.05%DMSO-d6) δ 7.61 (s, 1H), 7.44 (s, 1H), 7.15 (s, 1H), 3.83 (t, 2H), 3.32(S, 3H), 2.83 (s, 3H), 1.11 (d, 3H), 0.88 (m, 1H), 0.55 (m, 1H), 0.37(m, 1H). LCMS (M+H)=314.22

EXAMPLE 1 R, S, R Diastereomer

Step A. To a −70° C. solution containing 2.57 g (15.01 mmol) ofN-Boc-pyrrolidine in 75 mL of ether was added 1.4 M sec-BuLi (11.8 ml,16.5 mmol). The resulting reaction mixture was stirred at thistemperature for 4 h then treated with 4.94 g (15.01 mmol) ofN,N-dibenzyl-L-phenylalanal in 20 mL of ether. The reaction was completewithin 5 minutes. The reaction mixture was quenched with 50 mL ofsaturated NaHCO₃ and extracted with EtOAc (3×50 mL). The combinedorganic extracts were washed with water and brine (2×25 mL). Evaporationof the solvent and column chromatography (1:4 EtOAc/Hexanes) affordedthe (S, R, R) diastereomer and the (S, R, S) diasteromer. (S, R, R)Diastereomer: ¹H NMR (CDCl₃) δ 7.34–7.10 (m, 15H), 4.19 (m, 1H),3.82–2.90 (m, 9H), 1.83 (m, 2H), 1.47 (s, 9H), 1.26 (m, 4H). LCMS(M+H)=501.3. (S, R, S) Diastereomer: ¹H NMR (CDCl₃) δ 7.29 (m, 15H),4.96 (m, 1H), 3.96 (d, J=14.5 Hz, 2H), 3.78 (m 1H), 3.56 (d, J=14.5 Hz,2H), 3.33 (m, 3H), 3.07 (m, 1H), 2.84 (m, 2H), 1.83 (m, 4H), 1.47 (s,9H). LCMS (M+H)=501.3.

Step B. A solution containing 0.130 g (0.259 mmol) of the (S, R, R)dibenzylamine from step A and a catalytic amount of 10% Pd(OH)₂ in 5 mLof MeOH was hydrogenated under a balloon of hydrogen gas for 16 h. Themixture was filtered through a pad of Celite and evaporated to give thedesired amine as an oil. LCMS (M+H)=321.3.

Step C. A solution containing 92 mg (0.24 mmol) of the intermediate acidI in 5 mL of CH₂Cl₂ was treated sequentially with BOP reagent (103 mg,0.24 mmol), the (S, R, R) amine from step B (78 mg, 0.24 mmol), anddiisopropylethylamine (0.13 mL, 0.72 mmol). The reaction mixture wasstirred at ambient temperature for 30 minutes. Evaporation of thesolvent and purification reverse phase HPLC afforded the amide. LCMS(M+H)=679.3.

Step D. To 50 mg (0.074 mmol) of the Boc-protected amine from step Cdissolved in 3 mL CH₂Cl₂ was added Dess-Martin periodinane (0.094 g,0.222 mmol) and the solution was stirred at ambient temperature for 1 h.The solvent was evaporated and the crude solution was treated with 2.5mL CH₂Cl₂:TFA (4:1) and stirred 15 min at ambient temperature. Thereaction was evaporated and purified by reverse phase HPLC to afford thedesired compound as its TFA salt. ¹H NMR (CD₃OD) δ 8.88 (d, J=7.7 Hz,1H), 8.12 (s, 1H), 8.03 (s, 1H), 7.90 (s, 1H), 7.41–7.21 (m, 10H), 5.24(t, J=7.1 Hz, 1H), 4.71 (t, J=8.1 Hz, 1H), 3.35 (s, 3H), 3.40–3.30 (m,1H), 3.11 (dd, J=14, 9.4 Hz, 1H), 2.96 (s, 3H), 2.28 (m, 1H), 2.02–1.92(m, 2H), 1.82 (m, 2H), 1.58 (d, J=6.9 Hz, 3H). LCMS (M+H)=577.3.

EXAMPLE 2 R, S, S Diastereomer

Step A. A solution containing 146 mg (0.39 mmol) of the intermediateacid I in 5 mL of CH₂Cl₂ was treated sequentially with BOP reagent (164mg, 0.39 mmol), the (S, R, S) amine from Example 1, step B (150 mg, 0.48mmol), and diisopropylethylamine (0.21 mL, 1.17 mmol). The reactionmixture was stirred at ambient temperature for 30 minutes. Evaporationof the solvent and purification reverse phase HPLC to afford the amide.LCMS (M+H)=679.3.

Step B. To 50 mg (0.074 mmol) of the Boc-protected amine from step Adissolved in 3 mL of CH₂Cl₂ was added Dess-Martin periodinane (0.094 g,0.222 mmol) and the solution was stirred at ambient temperature for 1 h.The solvent was evaporated and the crude solution was treated with 2.5mL CH₂Cl₂:TFA (4:1) and stirred 15 min at ambient temperature. Thereaction was evaporated and purified by reverse phase HPLC to afford thedesired compound as its TFA salt. ¹H NMR (CD₃OD) δ 8.89 (d, J=7.7 Hz,1H), 8.12 (s, 1H), 8.02 (s, 1H), 7.91 (s, 1H), 7.41–7.24 (m, 10H), 5.24(m 1H), 5.07 (dd, J=9.4, 6.1 Hz, 1H), 4.37 (t, J=7.0, 1H), 3.48 (q,J=7.1 HZ, 1H), 3.35 (s, 3H), 3.10 (dd, J=14, 7.1 Hz, 1H), 2.95 (s, 3H),2.43 (m, 2H), 2.04 (m, 2H), 1.57 (d, J=7.1 Hz, 3H). LCMS (M+H)=577.2.

EXAMPLE 3 R, S, R Diastereomer

Step A. To a −70° C. solution containing 1.12 g (6.05 mmol) ofN-Boc-piperidine in 15 mL of ether was added TMEDA (0.77 g, 6.66 mmol)then 1.4 M sec-BuLi (4.76 ml, 6.66 mmol). The resulting reaction mixturewas stirred at this temperature for 1 h then, warmed to −20° C. for 10min, recooled to −70° C. then treated with 2.0 g (6.05 mmol) ofN,N-dibenzyl-L-phenylalanal in 5 mL of ether. The reaction was completewithin 10 minutes but was allowed to stir to rt over 4 h to effectcyclization of the undesired erythro isomer (e.g see Beak and Lee, J.Org. Chem. 1993, 58, 1109–1117). The reaction mixture was quenched with50 mL of saturated NaHCO₃ and extracted with EtOAc (3×50 mL). Thecombined organic extracts were washed with water and brine (2×25 mL).Evaporation of the solvent and column chromatography (1:4 EtOAc/Hexanes)afforded the diastereomerically pure alcohol. ¹H NMR (CDCl₃) δ 7.30 (m,15H), 4.40 (m, 1H), 4.15 (m, 1H), 3.83 (d, J=14 Hz, 2H), 3.73 (m, 1H),3.59 (d, J=14 Hz, 2H), 3.10–2.91 (m, 3H), 2.74 (m, 1H), 1.94 (m 1H),1.67–0.94 (m, 6H), 1.39 (s, 9H). LCMS (M+H)=515.4.

Step B. A solution containing 0.158 g (0.307 mmol) of the dibenzylaminefrom step A and a catalytic amount of 10% Pd(OH)₂ in 10 mL of MeOH washydrogenated under a balloon of hydrogen gas for 48 h. The mixture wasfiltered through a pad of Celite and evaporated to give the desiredamine as an oil. LCMS (M+H)=335.3.

Step C. A solution containing 90 mg (0.24 mmol) of the intermediate acidI in 5 mL of CH₂Cl₂ was treated sequentially with BOP reagent (101 mg,0.24 mmol), the amine from step B (80 mg, 0.24 mmol), anddiisopropylethylamine (0.13 mL, 0.72 mmol). The reaction mixture wasstirred at ambient temperature for 30 minutes. Evaporation of thesolvent and purification by silica gel chromatography (100% EtOAc)afforded the amide. ¹H NMR (CDCl₃) δ 7.93–7.10 (m, 14 H), 6.77 (d, J=7.4Hz, 1H), 5.26 (m, 1H), 4.41 (m, 1H), 4.32 (m, 1H), 4.07 (m, 1H), 3.28(s, 3H), 3.08 (m, 1H), 2.89 (s, 3H), 2.95–2.71 (m, 2H), 2.15 (m 1H),1.73–1.43 (m, 7H), 1.59 (d, J=7.0 Hz, 3 H), 1.51. (s, 9H). LCMS(M−BOC)=593.3.

Step D. To 65 mg (0.094 mmol) of the Boc-protected amine from step C wasdissolved in 3 mL of CH₂Cl₂ was added Dess-Martin periodinane (0.12 g,0.28 mmol) and the solution was stirred at ambient temperature for 2 h.The solvent was evaporated and the crude solution was treated with 2.5mL CH₂Cl₂:TFA (4:1) and stirred 15 min at ambient temperature. Thereaction was evaporated and purified by reverse phase HPLC to afford ofthe desired compound as its TFA salt. ¹H NMR (CD₃OD) δ 8.88 (d, J=7.42Hz, 1H), 8.13 (s, 1H), 8.04 (s, 1H), 7.92 (s, 1H), 7.42–7.20 (m, 10H),5.27 (m, 1H), 4.26 (dd, J=12, 3.0 Hz, 1H), 3.48–3.28 (m, 2H), 3.36 (s,3H), 3.10 (dd, J=13, 9.0 Hz, 1H), 2.97 (s, 3H), 2.22 (m, 1H), 1.85 (m,2H), 1.60 (d, J=7.0 Hz, 3H), 1.62–1.58 (m, 1H), 1.36–1.30 (m, 2H). LCMS(M+H)=591.3.

EXAMPLE 4

Step A. A solution containing 20.0 mg (0.054 mmol) of intermediate II in2 mL of CHCl₃ was treated sequentially with BOP reagent (24.0 mg, 0.054mmol), the amine intermediate III (19.0 mg, 0.064 mmol), anddiisopropylethylamine (0.021 mL, 0.12 mmol). The reaction mixture wasstirred at ambient temperature for ten minutes. Evaporation of thesolvent and purification by reverse phase HPLC afforded the aminoalcohol. ¹H NMR (CD₃OD) δ 8.87 (d, 1H), 8.32 (s, 1H), 7.98 (d, 2H), 7.78(s, 1H), 7.36 (m, 4H), 7.25 (m, 5H), 5.23 (m, 1H), 4.24 (m, 1H), 3.96(m, 1H), 3.33 (s, 3H), 3.19 (m, 2H), 2.94 (s, 3H), 2.80 (m, 3H), 1.57(d, 3H), 0.89 (m, 4H). LCMS (M+H)=597.3.

Step B. To the amino alcohol (0.204 g, 0.342 mmol) from step A in 5 mLacetonitrile was added di-tert-butyldicarbonate (0.097 g, 0.45 mmol)followed by diisopropylethylamine (0.13 g, 1.03 mmol). The reaction wasstirred at ambient temperature for 16 hours, concentrated in vacuo andpurified by silica gel chromatography (80% EtOAc/Hexanes) to afford theBoc-protected amine. LCMS (M+H)=697.1.

Step C. To 47 mg (0.067 mmol) of the Boc-protected amine from step Bdissolved in 3 mL CH₂Cl₂ was added Dess-Martin periodinane (0.086 g,0.202 mmol) and the solution was stirred at ambient temperature for 2 h.The solvent was evaporated and the crude solution was treated with 2.5mL CH₂Cl₂:TFA (4:1) and stirred 30 min at ambient temperature. Thereaction was evaporated and purified by reverse phase HPLC to afford thedesired compound as its TFA salt. ¹H NMR (CD₃OD) δ 8.89 (d, J=7.9 Hz,1H), 8.13 (s, 1H), 8.02 (s, 1H), 7.93 (s, 1H), 7.42 (dd, J=8.2, 5.4 Hz,2H), 7.34–7.24 (m, 5H), 7.06 (t, J=8.7 Hz, 2H), 5.24 (m, 1H), 4.81 (m,1H), 4.39 (d, J=18 Hz, 1H), 3.97 (d, J=18 Hz, 1H), 3.36 (s, 3H), 3.14(dd, J=14, 9.1 Hz, 1H), 2.96 (s, 3H), 2.70 (m, 1H), 1.57 (d, J=7.1 Hz,3H), 0.96–0.83 (m 5H). LCMS (M+H)=595.3.

EXAMPLE 5 R, S, R, S Diastereomer

Step A. To a stirred mixture of 1.1 g (6.1 mmol) of(S)-N-Boc-2-methylpyrrolidine (preparation: Donner, B. G. TetrahedronLetters 1995, 36, 1223–1226) and 0.70 g (6.08 mmol)N,N,N′,N′-tetramethylethylenediamine in 12 mL of ether at −78° C., 5.2mL of 1.4M sec-butyllithium was added dropwise. The reaction mixture wasstirred at −78° C. for 40 min. A solution of theN,N-dibenzyl-L-phenylalanal in 6 mL ether was then added to the reactionmixture. The reaction was warmed to room temperature over 16 h. Thereaction was quenched with 100 mL of saturated bicarb and the mixturewas extracted with EtOAc (3×50 mL). The combined organics were washedwith brine (100 mL) before being dried over MgSO₄, filtered, andconcentrated in vacuo. The residue was purified by silica gelchromatography (5%–60% EtOAc:Hexanes). The isolated product was thenpurified by reverse phase HPLC. Lyophilization provided thedibenzylamine. ¹H NMR (CD₃OD) δ 8.87 (s, 1H), 8.10 (s, 1H), 7.91 (s,1H), 7.77 (d, J=7.7 Hz, 1H), 7.65–7.14 (m, 13 H), 5.24 (m, 1H), 4.21 (m,1H), 3.97 (m, 1H), 3.21 (m, 1H), 2.78 (m, 2H), 2.28 (m, 1H), 2.26 (s,3H), 1.56 (d, J=7.1 Hz, 3H), 0.91 (m, 4H). LCMS (M+H)=515.4.

Step B. A solution containing 0.031 g (0.060 mmol) of from step A in 1mL MeOH was treated with a catalytic amount of Pearlman's catalyst andstirred at room temperature under a hydrogen atmosphere for 40 min. Thereaction was filtered through plug of celite and the solvent was removedin vacuo to afford the corresponding amine. LCMS (M+H)=335.4.

Step C: A solution containing 22 mg (0.055 mmol) of the intermediateacid II in 3 mL of CH₂Cl₂ was treated sequentially with BOP reagent (24mg, 0.055 mmol), the (S, R, R) amine from step B (20 mg, 0.055 mmol),and diisopropylethylamine (0.03 mL, 0.167 mmol). The reaction mixturewas stirred at ambient temperature for 30 minutes. Evaporation of thesolvent and purification reverse phase HPLC to afford the amide. LCMS(M+H)=711.3.

Step D. A solution containing 0.0092 g (0.013 mmol) of amide from step Cin 1 mL CH₂Cl₂ at 0° C. was treated with 0.011 g (0.026 mmol) ofDess-Martin periodinane. The reaction mixture was warmed to roomtemperature and stirred for 1 h. The solvent was removed in vacuo andthe residue was purified by reverse phase HPLC. Lyophilization providedthe ketone. LCMS (M-Boc)=609.3.

Step E. A solution containing 0.0081 g (0.011 mmol) of the ketone fromstep D in 1 mL CH₂Cl₂ at 0° C. was treated with 1 mL TFA. The reactionwas stirred at 0° C. for 10 min. The solvents were removed in vacuo toafford the desired amino ketone. LCMS (M+H)=609.6. ¹H NMR (CD₃OD) δ 8.90(d, J=7.7 Hz, 1 H), 8.11 (m, 1H), 8.03 (m, 1H), 7.90 (m, 1H), 7.42 (m,2H), 7.30–7.19 (m, 4H), 7.06 (t, 2H), 5.23 (m, 1H), 4.76 (m, 1H), 3.66(m, 1H), 3.35 (s, 3H), 3.11 (m, 1H), 2.96 (s, 3H), 2.39 (m, 1H), 2.15(m, 1H), 1.81 (m, 2H), 1.72–1.62 (m, 2H), 1.57 (d, J=7.0 Hz, 3H), 1.40(d, J=6.6 Hz, 3H).

EXAMPLE 6 Trans (RR,SS), S

Step A: A solution containing 0.25 g (0.80 mmol) of the intermediateacid VI in 10 mL of CH₂Cl₂ was treated sequentially with BOP reagent(0.338 g, 0.80 mmol), the amine from intermediate III (0.234 mg, 0.80mmol), and diisopropylethylamine (0.31 g, 2.40 mmol). The reactionmixture was stirred at ambient temperature for 30 minutes. Evaporationof the solvent and purification with reverse phase HPLC afforded theamide. LCMS (M+H)=516.3.

Step B. A solution containing 0.31 g (0.61 mmol) of amide from step A,0.16 g (0.73 mmol) of di-tert-butyl dicarbonate: and 0.094 g (0.73 mmol)of DIPEA was stirred in 6 mL of ACN at 50° C. for 1.5 h. The reactionmixture was cooled and the solvent was removed in vacuo to afford theBoc amine. LCMS (M−Boc)=616.4.

Step C. A solution containing 0.33 g (0.53 mmol) of the Boc amine fromstep B in 5 mL CH₂Cl₂ at 0° C. was treated with 0.45 g (0.11 mmol) ofDess-Martin periodinane. The reaction mixture was warmed to roomtemperature and stirred for 30 min. The solvent was removed in vacuo andthe residue was purified by reverse phase HPLC. Lyophilization providedthe Boc amino ketone. LCMS (M−Boc)=514.3.

Step D. A solution containing 0.16 g (0.26 mmol) of Boc-amino ketonefrom step C in 2 mL CH₂Cl₂ at 0° C. was treated with 2 mL TFA. Thereaction was stirred at 0° C. for 10 min. The solvents were removed invacuo and the residue was purified by reverse phase HPLC. Lyophilizationprovided the desired amino ketone. LCMS (M+H)=514.2. ¹H NMR (CD₃OD) δ7.33–7.24 (m, 5H), 7.19–7.16 (m, 3H), 4.78 (m, 1H), 3.86 (m, 2H), 3.14(m, 2H), 2.91 (s, 6H), 2.70 (m, 2H), 1.18 (t, 1H), 1.09 (d, J=6.0 Hz,3H), 1.00 (m, 2H), 0.86 (m, 4H), 0.53 (m, 1H), 0.38 (m, 1H).

EXAMPLE 7 [CIS (RS, SR)], S

Step A. A solution containing 0.32 g (1.3 mmol) of the intermediate IV,0.33 g (2.5 mmol) of 1-bromo-2-butyne, and 0.35 g (2.5 mmol) K₂CO₃ in12.5 mL of acetonitrile was heated at reflux for 4 h. The reactionmixture was cooled and diluted with 60 mL of H₂O. The mixture wasextracted with of EtOAc (3×60 mL). The combined organics were washedwith brine (60 mL) then dried (MgSO₄). The solvent was removed in vacuoand purified by silica gel chromatography (20%–50% EtOAc:Hex) to affordalkynyl aniline. LCMS (M+H)=311.2.

Step B. A solution containing 0.083 g (0.27 mmol) of alkynyl anilinefrom step A in 3 mL MeOH was treated with a catalytic amount ofLindlar's catalyst and stirred at room temperature under a hydrogenatmosphere for 10 min. The reaction was filtered through plug of silicagel and the solvent was removed in vacuo. Purification by reverse phaseHPLC afforded Z-alkenyl aniline. LCMS (M+H)=313.2.

Step C. A solution containing 0.038 g (0.12 mmol) Z-alkenyl aniline fromstep B in 2.5 mL EtOAc at 0° C. was treated with 0.058 g (1.3 mmol) offreshly prepared diazomethane and a catalytic amount of palladium(II)acetate and stirred at 0° C. for 15 min. The reaction was filteredthrough a plug of silica gel. Evaporation of the solvent left the methylcyclopropyl methyl aniline. LCMS (M+H)=327.2.

Step D. To 0.034 g (0.10 mmol) of the methyl cyclopropyl methyl anilinefrom step C in 5 mL THF:MeOH (1:1) was added 2 N NaOH (0.15 mL, 0.30mmol). The solution was heated to 50° C. for 1 h. After cooling thesolution was acidified by the addition of 1 N HCl (20 mL) and extractedwith EtOAc (3×30 mL). The combined organic extracts were dried overMgSO₄, filtered, and concentrated in vacuo to the desired carboxylicacid. LCMS (M+H)=313.2.

Step E: A solution containing 0.020 g (0.060 mmol) of the carboxylicacid from step D in 10 mL of CH₂Cl₂ was treated sequentially with BOPreagent (0.026 g, 0.060 mmol), the amine from intermediate III (0.018 g,0.060 mmol), and diisopropylethylamine (0.023 g, 0.180 mmol). Thereaction mixture was stirred at ambient temperature for 30 minutes.Evaporation of the solvent and purification with reverse phase HPLCafforded the amide. LCMS (M+H)=515.3. ¹H NMR (CD₃OD) δ 7.27 (m, 4H),7.16 (m, 1H), 7.15–6.91 (m, 3H), 4.22 (m, 1H), 4.01 (m, 1H), 3.27 (m,2H), 3.20–3.06 (m, 2H), 2.90 (s, 3H), 2.89 (s, 3H), 2.87–2.75 (m, 2H),2.02 (d, J=7.7, 3H), 1.71 (m, 1H), 1.24 (t, 2H), 1.06 (m, 2H), 0.99–0.87(m, 4H).

Step F. A solution containing 0.051 g (0.10 mmol) of the amide from stepE, 0.026 g (0.12 mmol) of di-tert-butyl dicarbonate, and 0.016 g (1.2mmol) of DIPEA was stirred in 1 mL of ACN at 50° C. for 1.5 h. Thereaction mixture was cooled and the solvent was removed in vacuo toafford the Boc amine. LCMS (M+H)=615.3.

Step G. A solution containing 0.062 g (0.10 mmol) of the Boc amine fromstep F in 1 mL CH₂Cl₂ at 0° C. was treated with 0.042 g (0.10 mmol) ofDess-Martin periodinane. The reaction mixture was warmed to roomtemperature and stirred for 1 h. The solvent was removed in vacuo andthe residue was purified by reverse phase HPLC. Lyophilization providedthe Boc-amino ketone. LCMS (M−Boc)=513.3.

Step H. A solution containing 0.0080 g (0.013 mmol) of Boc-amino ketonefrom step G in 1 mL CH₂Cl₂ at 0° C. was treated with 1 mL TFA. Thereaction was stirred at 0° C. for 10 min. The solvents were removed invacuo to afford the desired amino ketone. LCMS (M+H)=513.3. ¹H NMR(CD₃OD) δ 7.35–7.24 (m, 5H), 7.04 (m, 2H), 6.94 (m, 1H), 4.76 (m, 1H),4.39 (m, 2H), 4.05 (m, 2H) 3.29 (s, 3H), 3.22–3.04 (m, 2H), 2.92 (s,3H), 2.74 (m, 2H), 1.76 (m, 2H), 1.29 (m, 3H), 1.12 (m, 1H), 0.97–0.85(m, 4H).

EXAMPLE 8 [TRANS (RR, SS)], S

Step A. A solution containing 0.14 g (0.53 mmol) of intermediate IV,0.072 g (0.53 mmol) of trans-crotyl bromide, and 0.073 g (0.53 mmol)K₂CO₃ in 5 mL of acetonitrile was heated at reflux for 2 h. The reactionmixture was cooled and diluted with 12 mL of H₂O. The mixture wasextracted with 3×12 mL of EtOAc. The combined organics were washed withbrine (12 mL) before being dried (MgSO₄). The solvent was removed invacuo and purified by silica gel chromatography (20%–50% EtOAc:Hex) toafford the alkenyl aniline. LCMS (M+H)=313.2.

Step B. A solution containing 0.064 g (0.21 mmol) alkenyl aniline fromstep A in 7 mL EtOAc at 0° C. was treated with 0.18 g (4.1 mmol) offreshly prepared diazomethane and a catalytic amount of palladium(II)acetate and stirred at 0° C. for 15 min. The reaction was filteredthrough a plug of silica gel. Evaporation of the solvent left the methylcyclopropyl methyl aniline. LCMS (M+H)=327.2.

Step C. To 0.067 g (0.21 mmol) of the methyl cyclopropyl methyl anilinefrom step C in 5 mL THF:MeOH (1:1) was added 2 N NaOH (0.31 mL, 0.63mmol). The solution was heated to 50 C for 1 h. After cooling thesolution was acidified by the addition of 1 N HCl (20 mL) and extractedwith EtOAc (3×30 mL). The combined organic extraction were dried overMgSO₄, filtered, and concentrated in vacuo to yield of the desiredcarboxylic acid. LCMS (M+H)=313.2.

Step D: A solution containing 0.032 g (0.10 mmol) of the carboxylic acidfrom step Cin 10 mL of CH₂Cl₂ was treated sequentially with BOP reagent(0.043 g, 0.10 mmol), the amine from intermediate m (0.029 g, 0.10mmol), and diisoptopylethylamine (0.039 g, 0.30 mmol). The reactionmixture was stirred at ambient temperature for 30 minutes. Evaporationof the solvent and purification with reverse phase HPLC afforded theamide. LCMS (M+H)=515.3. ¹H NMR (CD₃OD) δ 7.26 (m, 4H), 7.19–6.89 (m,4H), 4.23 (m, 1H), 3.98 (m, 1H), 3.63–3.29 (m, 2H), 3.07 (m, 2H), 2.91(s, 3H), 2.90 (s, 3H), 2.88–2.73 (m, 2H), 1.68 (m, 1H), 1.04 (d, J=6.1,3H), 0.97–0.87 (m, 4H), 0.45 (m, 2H), 0.32 (m, 2H).

Step E. A solution containing 0.020 g (0.040 mmol) of the amide fromstep D, 0.010 g (0.050 mmol) of di-tert-butyl dicarbonate, and 0.0060 g(0.050 mmol) of DIPEA was stirred in 1 mL of ACN at 50° C. for 1 h. Thereaction mixture was cooled and the solvent was removed in vacuo toafford the Boc amine. LCMS (M−Boc)=515.3.

Step F. A solution containing 0.025 g (0.040 mmol) of the Boc amine fromstep E in 1 mL CH₂Cl₂ at 0° C. was treated with 0.034 g (0.080 mmol) ofDess-Martin periodinane. The reaction mixture was warmed to roomtemperature and stirred for 20 min. The solvent was removed in vacuo andthe residue was purified by reverse phase HPLC. Lyophilization providedthe Boc-amino ketone. LCMS (M−Boc)=513.3.

Step G. A solution containing 0.0050 g (0.0080 mmol) of Boc-amino ketonefrom step F in 0.5 mL CH₂Cl₂ at 0° C. was treated with 0.5 mL TFA. Thereaction was stirred at 0° C. for 10 min. The solvents were removed invacuo to afford the desired amino ketone. LCMS (M+H)=513.3. ¹H NMR(CD₃OD) δ 7.29 (m, 5H), 7.01 (m, 2H), 6.88 (m, 1H), 4.74 (m, 1H), 4.37(m, 2H), 4.03 (m, 2H), 3.14 (m, 2H), 2.91 (s, 3H), 2.90 (s, 3H), 1.71(m, 2H), 1.29 (s, 4H), 1.17 (m, 1H), 1.02 (m, 1H), 0.87 (m, 3H), 0.69(m, 1H).

EXAMPLE 9

Step A. A solution containing 0.030 g (0.10 mmol) of the carboxylic acidIntermediate V in 5 mL of CH₂Cl₂ was treated sequentially with BOPreagent (0.043 g, 0.10 mmol), amine Intermediate III (0.029 g, 0.10mmol), and diisopropylethylamine (0.039 g, 0.30 mmol). The reactionmixture was stirred at ambient temperature for 10 minutes before thesolvent was evaporated. The resulting residue was purified by reversephase HPLC to yield the desired amide.

Step B. A solution containing 0.050 g (0.10 mmol) of the amine from stepA, 0.022 g (0.10 mmol) of di-tert-butyl dicarbonate, and 0.012 g (0.10mmol) of DIPEA was stirred in 1 mL of ACN at 45° C. for 3 h. Thereaction mixture was cooled and the solvent was removed in vacuo toafford the Boc amine that was used without further purification.

Step C. A solution containing 0.020 g (0.040 mmol) of the amine fromstep B in 1 mL CH₂Cl₂ at 0° C. was treated with 0.034 g (0.080 mmol) ofDess-Martin periodinane. The reaction mixture was warmed to roomtemperature and stirred for 20 min. The solvent was removed in vacuo andthe residue was purified by reverse phase HPLC. Lyophilization providedBoc-amino ketone. This compound was dissolved in EtOAc at 0° C. andtreated directly with HCl gas for 5 minutes. The reaction mixture wasstirred for 1 h, the solvent was evaporated and the residue was purifiedby reverse phase chromatography. LCMS (M−Boc)=500.6. ¹H NMR (CDCl₃) δ7.29 (m, 8H), 5.88 (m, 1H), 5.10 (m, 1H), 4.75 (dd, 1H), (d, 1H), 4.00(d, 1H), 3.14 (dd, 1H), 2.72 (m, 1H), 2.43 (m, 1H), 2.11 (m, 2H), 1.99(m, 1H), 1.33 (d, 2H), 0.86 (m, 2H).

EXAMPLE 10

A 0° C. solution containing 30 mg (0.050 mmol) of the aryl ether fromExample 9, step B in 5 mL of DCM was treated with 5 mL of TFA. Thereaction was allowed to stir for 2 h before the solvents were evaporatedand the residue purified using reverse phase chromatography. ¹H NMR(CDCl₃) δ 7.28 (m, 8H), 4.75 (dd, 1H), 4.37 (d, 1H), 4.00 (d, 1H), 3.14(dd, 1H), 2.72 (m, 1H), 2.43 (m, 2H), 2.11 (m, 2H), 1.99 (m, 2H), 0.86(m, 2H).

EXAMPLE 11

Step A: A solution of methyl 3,5-dihydroxybenzoate (1.00 g, 2.96 mmol)and K₂CO₃ (1.6 g, 5.92 mmol) in dry acetone (35 mL) was treated with(bromomethyl)cyclopropane (0.40 g, 2.96 mmol). The mixture was refluxedfor 12 h. After cooling, the solution was made acidic with 1N HCl andextracted with EtOAc (3×50 mL). The combined organic layers were driedover MgSO₄, filtered and concetrated. Purification by silica gelchromatography (20% EtOAc/Hexanes) provided the mono phenol. LCMS(M+H)=223.2. ¹H NMR (CDCl₃) δ 7.16 (s, 1H), 7.13 (s, 1H), 6.64 (s, 1H),6.13 (s, 1H), 3.90 (s, 3H)m 3.81 (d, J=6.9 Hz, 2H), 1.23 (m, 1H), 0.65(m, 2H), 0.34 (m, 2H)

Step B: To a −78° C. solution of the phenol (0.63 g, 2.8 mmol) from step1 in dichloromethane (20 mL) was added DIPEA (0.4 g, 3.1 mmol) followedby triflic anhydride (0.87 g, 3.1 mmol). The solution was allowed towarm slowly to RT over 12 h after which the reaction was quenched by theaddition of saturated sodium bicarbonate (20 mL). The organic layer wasseperated and washed sequentially with 1N HCl (1×20 mL), H₂O (1×20 mL),and brine (1×20 mL). The organic layer was dried over MgSO₄, filteredand concentrated in vacuo. Purification by silica gel chromatography(10% EtOAc/Hexanes) provided the triflate. ¹H NMR (CDCl₃) δ 7.58 (s,1H), 7.50 (s, 1H), 7.01 (s, 1H), 3.94 (s, 3H), 3.88 (d, J=7.0 Hz, 2H),1.28 (m, 1H), 0.69 (m, 2H), 0.39 (m 2H).

Step C: A solution of the triflate from step 2 (0.30 g, 0.85 mmol),CsCO₃ (0.42 g, 1.28 mmol), and 2-cyanoarylboronic acid (0.22 g, 1.0mmol) was degassed under vacuum. Pd(PPh₃)₄ (0.98 g, 0.09 mmol) was thenadded and the reaction mixture was heated to 90° C. for 1 h. Water (60mL) was added followed by extraction with EtOAc (3×30 mL). The combinedorganic layers were dried over MgSO₄, filtered, and concetrated invacuo. Purification by silica gel chromatography (10% EtOAc/Hexanes)provided the biarylester. LCMS (M+H)=308.3. ¹H NMR (CDCl₃) δ 7.78–7.31(m 7H), 3.93 (s, 3H), 3.92 (d, J=7.0 Hz, 2H), 1.28 (m 1H), 0.68 (m 2H),0.38 (m, 2H).

Step D. A solution of 0.036 g (0.12 mmol) of ester from step 3 in 2 mLof a 1:1 mixture of THF:MeOH was treated with 0.18 mL 2N NaOH. Thereaction mixture was stirred for 1 h at 50° C. then cooled to roomtemperature. The reaction was quenched to a pH=2 with 1N HCl. Themixture was extracted with 3×25 mL of EtOAc. The combined organics werewashed with water (20 mL) and brine (20 mL) before being dried (MgSO₄).Evaporation of the solvent afforded the carboxylic acid. LCMS(M+1)=294.13.

Step E. A solution containing 0.083 g (0.28 mmol) of acid from step 4,0.12 g (0.42 mmol) of amine 1, 0.12 g (0.28 mmol) of BOP reagent, and0.11 g (0.84 mmol) of N,N-diisopropylethylamine in 3 mL CH₂Cl₂ wasstirred at room temperature for 12 h. The solvent was removed in vacuoand the residue was purified by reverse phase HPLC. Lyophilizationprovided the hydroxylamine. LCMS (M+1)=496.14. ¹H NMR (CD₃OD) δ 7.83 (d,J=7.7, 1H), 7.75 (t, 1H), 7.55 (t, 2H), 7.37 (s, 1H), 7.31–7.23 (m, 6H),7.18–7.15 (t, 1H), 4.6 (m, 1H), 4.0 (m, 1H), 3.89 (d, J=6.9, 2H), 3.34(m, 2H), 3.18 (m, 1H), 2.84 (m, 1H), 2.76 (m, 1H), 1.31–1.23 (m, 1H),0.97–0.86 (m, 4H), 0.63 (d, J=8.1, 2H), 0.37 (d, J=4.8).

Step F. A solution containing 0.14 g (0.28 mmol) of amine from step 5,0.074 g (0.34 mmol) of di-tert-butyl dicarbonate, and 0.060 g (0.34mmol) of DIPEA was stirred in 6 mL of ACN at 50° C. for 1 h. Thereaction mixture was cooled and the solvent was removed in vacuo toafford the Boc protected amine. LCMS (M+1–100)=496.09.

Step G. A solution containing 0.17 g (0.28 mmol) of the Boc protectedamine from step 6 in 2 mL CH₂Cl₂ at 0° C. was treated with 0.24 g (0.56mmol) of Dess-Martin periodinane. The reaction mixture was warmed toroom temperature and stirred for 30 min. The solvent was removed invacuo and the residue was purified by reverse phase HPLC. Lyophilizationprovided the desired Boc protected amino-ketone. LCMS (M+1–100)=494.09.

Step H. A solution containing 0.11 g (0.19 mmol) of ketone from step 7in 2 mL CH2Cl2 at 0° C. was treated with 2 mL TFA. The reaction wasstirred at 0° C. for 10 min. then room temperature for 10 min. Thesolvents were removed in vacuo and the residue was purified by reversephase HPLC. Lyophilization provided the desired amino-ketone. LCMS(M+1)=494.11. ¹H NMR (CD₃OD) δ 7.83 (d, J=7.7, 1H), 7.74 (t, 1H), 7.56(m, 2H), 7.50 (s, 1H), 7.36 (s, 1H), 7.30 (m, 5H), 7.23 (m, 1H), 4.80(dd, J=5.5, 9.2, 1H), 4.41 (d, J=17.9, 1H), 4.08 (d, J=17.8, 1H), 3.91(d, J=17.0, 2H), 3.37–3.28 (m, 1H), 3.14 (m, 1H), 2.72 (m, 1H),1.32–1.25 (m, 1H), 0.90–0.82 (m, 4H), 0.93 (d, J=8.1, 2H), 0.37 (d,J=4.8).

EXAMPLE 12 R, S, R, R Diastereomer

Step A. To a −70° C. solution containing 2.57 g (15.01 mmol) ofN-Boc-4-pyrrolidine in 75 mL of ether was added 1.4 M sec-BuLi (11.8 ml,16.5 mmol). The resulting reaction mixture was stirred at thistemperature for 4 h then treated with 4.94 g (15.01 mmol) ofN,N-dibenzyl-L-phenylalanal in 20 mL of ether. The reaction was completewithin 5 minutes. The reaction mixture was quenched with 50 mL ofsaturated NaHCO₃ and extracted with EtOAc (3×50 mL). The combinedorganic extracts were washed with water and brine (2×25 mL). Evaporationof the solvent and column chromatography (1:4 EtOAc/Hexanes) separatedthe (S, R, R) diastereomer and the (S, R, S) diastereomer.

(S, R, R) Diastereomer: ¹H NMR (CDCl₃) δ 7.34–7.10 (m, 15 H), 4.19 (m,1H), 3.82–2. (m, 9H), 1.83 (m, 2H), 1.47 (s, 9H), 1.26 (m, 4H). LCMS(M+H)=501.3.

(S, R, S) Diastereomer: ¹H NMR (CDCl₃) δ 7.29 (m, 15 H), 4.96 (m, 1H),3.96 (d, J=14.5 Hz, 2H), 3.78 (m 1H), 3.56 (d, J=14.5 Hz, 2H), 3.33 (m,3H), 3.07 (m, 1H), 2.84 (m, 2H), 1.83 (m, 4H), 1.47 (s, 9H). LCMS(M+H)=501.3

Step B. A solution containing 0.130 g (0.259 mmol) of the (S, R, R)dibenzylamine from step A and a catalytic amount of 10% Pd(OH)₂ in 5 mLof MeOH was hydrogenated under a balloon of hydrogen gas for 16 h. Themixture was filtered through a pad of Celite and evaporated to give thedesired amine as an oil. LCMS (M+H)=321.3

Step C. A solution containing 92 mg (0.24 mmol) of the intermediate acidI in 5 mL of CH₂Cl₂ was treated sequentially with BOP reagent (103 mg,0.24 mmol), the (S, R, R) amine from step B (78 mg, 0.24 mmol), anddiisopropylethylamine (0.13 mL, 0.72 mmol). The reaction mixture wasstirred at ambient temperature for 30 minutes. Evaporation of thesolvent and purification with reverse phase HPLC gave the amide. LCMS(M+H)=679.3.

Step D. A solution containing 73 mg (0.108 mmol) of the Boc-protectedamine from step C in 6 mL CH₂Cl₂:TFA (4:1) was stirred 45 min at ambienttemperature. The reaction was cooled, evaporated and purified by reversephase HPLC to afford the desired compound as its TFA salt. (S, R, R)Diastereomer: ¹H NMR (CD₃OD) δ 8.86 (d, J=7.3 Hz, 1H), 8.42 (d, J=9.0Hz, 1H), 7.97 (s, 2H), 7.74 (s, 1H), 7.40–7.10 (m, 10H), 5.22 (q, J=7.1Hz, 1H), 4.18 (m, 1H), 4.04 (dd, J=9.4, 2.2 Hz, 1H), 3.74 (t, J=7.0 Hz,1H), 3.40–3.26 (m, 2H), 3.33 (s, 3H), 2.94 (s, 3H), 2.81 (t, J=11.0 Hz,1H), 2.19–2.07 (m, 2H), 2.01 (m, 1H), 1.57 (d, J=7.0 Hz, 3H). LCMS(M+H)=579.2

EXAMPLE 13 R, S, R, S Diastereomer

Step A. A solution containing 146 mg (0.39 mmol) of the intermediateacid I in 5 mL of CH₂Cl₂ was treated sequentially with BOP reagent (164mg, 0.39 mmol), the (S, R, S) amine from Example 12, step B (150 mg,0.48 mmol), and diisopropylethylamine (0.21 mL, 1.17 mmol). The reactionmixture was stirred at ambient temperature for 30 minutes. Evaporationof the solvent and purification with reverse phase HPLC gave the amide.LCMS (M+H)=679.3.

Step B. A solution containing 32 mg (0.047 mmol) of the Boc-protectedamide from step A in 2.5 mL CH₂Cl₂:TFA (4:1) was stirred 30 min atambient temperature. The reaction was cooled, evaporated and purified byreverse phase HPLC to provide the desired compound as its TFA salt. ¹HNMR (CD₃OD) δ 8.87 (d, J=8.4 Hz, 1H), 8.47 (d, J=8.4 Hz, 1H), 8.04 (s,1H), 7.99 (s, 1H), 7.82 (s, 1H), 7.42–7.14 (m, 9H), 7.16 (t, J=7.3 Hz,1H), 5.24 (q, J=7.0 Hz, 1H), 4.29 (m, 1H), 3.74 (m, 2H), 3.53–3.33 (m,3H), 3.35 (s, 3H), 2.95 (s, 3H), 2.81 (m, 1H), 2.15 (m, 2H), 2.03 (m2H), 1.59 (d, J=7.3 Hz, 3H). LCMS (M+H)=579.3.

EXAMPLE 14 R, S, R, R Diastereomer

Step A. A solution containing 27 mg (0.069 mmol) of the p-fluoro acidintermediate II in 2 mL of CH₂Cl₂ was treated sequentially with BOPreagent (0.030 mg, 0.069 mmol), the (S, R, R) amine from Example 12,step A (78 mg, 0.24 mmol), and diisopropylethylamine (0.033 mL, 0.188mmol). The reaction mixture was stirred at ambient temperature for 30minutes. Evaporation of the solvent and purification by reverse phaseHPLC afforded the amide. LCMS (M+H)=697.2.

Step B. A solution containing 18 mg (0.026 mmol) of the Boc-protectedamine from step A in 2 mL CH₂Cl₂:TFA (4:1) was stirred 2 h at ambienttemperature. The reaction was cooled, evaporated and purified by reversephase HPLC to provide the desired compound as its TFA salt. ¹H NMR(CD₃OD) δ 8.86 (m, 1H), 8.43 (d, J=8.2 Hz, 1H), 7.97 (s, 2H), 7.75 (s,1H), 7.41–7.06 (m, 9H), 5.22 (m, 1H), 4.18 (m, 1H), 4.04 (m 1H), 3.73(m, 1H), 3.40–3.26 (m, 2H), 3.33 (s, 3H), 2.94 (s, 3H), 2.81 (m, 1H),2.19–1.99 (m, 3H), 1.56 (d, J=6.1, 3H). LCMS (M+H)=597.2

EXAMPLE 15 R, S, R, R Diastereomer

Step A. To a −70° C. solution containing 1.12 g (6.05 mmol) ofN-Boc-4-piperidine in 15 mL of ether was added TMEDA (0.77 g, 6.66 mmol)then 1.4 M sec-BuLi (4.76 ml, 6.66 mmol). The resulting reaction mixturewas stirred at this temperature for 1 h then, warmed to −20° C. for 10min, recooled to −70° C. then treated with 2.0 g (6.05 mmol) ofN,N-dibenzyl-L-phenylalanal in 5 mL of ether. The reaction was completewithin 10 minutes but was allowed to stir to rt over 4 h to effectcyclization of the undesired erythro isomer (e.g see Beak and Lee, J.Org. Chem. 1993, 58, 1109–1117). The reaction mixture was quenched with50 mL of saturated NaHCO₃ and extracted with EtOAc (3×50 mL). Thecombined organic extracts were washed with water and brine (2×25 mL).Evaporation of the solvent and column chromatography (1:4 EtOAc/Hexanes)afforded the diastereomerically pure alcohol. ¹H NMR (CDCl₃) δ 7.30 (m,15 H), 4.40 (m, 1H), 4.15 (m, 1H), 3.83 (d, J=14 Hz, 2H), 3.73 (m, 1H),3.59 (d, J=14 Hz, 2H), 3.10–2.91 (m, 3H), 2.74 (m, 1H), 1.94 (m 1H),1.67–0.94 (m, 6H), 1.39 (s, 9H). LCMS (M+H)=515.4.

Step B. A solution containing 0.158 g (0.307 mmol) of the dibenzylaminefrom step A and a catalytic amount of 10% Pd(OH)₂ in 10 mL of MeOH washydrogenated under a balloon of hydrogen gas for 48 h. The mixture wasfiltered through a pad of Celite and evaporated to give 0.080 g (78%) ofthe desired amine as an oil. LCMS (M+H)=335.3.

Step C. A solution containing 90 mg (0.24 mmol) of the intermediate acidI in 5 mL of CH₂Cl₂ was treated sequentially with BOP reagent (101 mg,0.24 mmol), the amine from step B (80 mg, 0.24 mmol), anddiisopropylethylamine (0.13 mL, 0.72 mmol). The reaction mixture wasstirred at ambient temperature for 30 minutes. Evaporation of thesolvent and purification by silica gel chromatography (100% EtOAc)afforded the amide. ¹H NMR (CDCl₃) δ 7.93–7.10 (m, 14 H), 6.77 (d, J=7.4Hz, 1H), 5.26 (m, 1H), 4.41 (m, 1H), 4.32 (m, 1H), 4.07 (m, 1H), 3.28(s, 3H), 3.08 (m, 1H), 2.89 (s, 3H), 2.95–2.71 (m, 2H), 2.15 (m 1H),1.73–1.43 (m, 7H), 1.59 (d, J=7.0 Hz, 3 H), 1.51. (s, 91) LCMS(M−BOC)=593.3.

Step D. A solution containing 34 mg (0.05 mmol) of the Boc protectedamine from step C in 2.5 mL CH₂Cl₂:TFA (4:1) was stirred 15 min atambient temperature. The reaction was cooled, evaporated and purified byreverse phase HPLC to afford the desired compound as its TFA salt. ¹HNMR (CD₃OD) δ 8.87 (d, J=7.3 Hz, 1H), 8.39 (d, J=9.1 Hz, 1H), 7.98 (s,2H), 7.76 (s, 1H), 7.42–7.11 (m, 10 H), 5.24 (q, J=7.0 Hz, 1H), 4.23 (m,1H), 3.91 (d, J=8.0 Hz, 1H), 3.33 (m, 1H), 3.34 (s, 3H), 3.22 (d, J=12Hz, 1H), 3.04 (m, 1H), 2.95 (s, 3H), 2.82 (m, 1H), 2.17 (d, J=12 Hz,1H), 1.95–1.45 (m, 5H), 1.58 (d, J=7.0 Hz, 3H). LCMS (M+H)=593.3.

EXAMPLE 16 R, S, R, R Diastereomer

Step A. To a −70° C. solution containing 3.28 g (13.6 mmol) ofN-Boc-4-piperidone ethylene ketal in 30 mL of ether was added TMEDA(1.91 g, 16.4 mmol) then 1.4 M sec-BuLi (12.6 ml, 16.4 mmol). Theresulting reaction mixture was stirred at this temperature for 4 h thentreated with 5.4 g (16.4 mmol) of N,N-dibenzyl-L-phenylalanal in 25 mLof ether. The reaction was complete within 10 minutes but was allowed tostir to rt over 4 h to effect cyclization of the undesired erythroisomer (e.g see Beak and Lee, J. Org. Chem. 1993, 58, 1109–1117). Thereaction mixture was quenched with 50 mL of saturated NH₄Cl and dilutedwith 100 mL of ether. The organic phase was separated and washed withwater and brine (2×25 mL). Evaporation of the solvent and columnchromatography (1:4 EtOAc/Hexanes) afforded the diastereomerically purealcohol. ¹H NMR (CDCl₃) δ 7.38–6.95 (m, 15H), 4.41 (bs, 1H), 4.00–3.80(m, 8H), 3.53 (m, 2H), 3.22 (bt, 1H), 3.10–2.80 (m, 2H), 2.00–1.60 (m,5H), 1.25 (s, 9H). LCMS (M+H)=573.38.

Step B. A solution containing 3.2 g (5.5 mmol) of the dibenzylamine fromstep A and 1.5 g of 10% Pd(OH)₂ in 100 mL of MeOH was hydrogenated undera balloon of hydrogen gas for 3 h. The mixture was filtered through apad of Celite and evaporated to give the desired amine as an oil. ¹H NMR(CDCl₃) δ 7.31–7.22 (m, 5H), 4.48 (bs, 1H), 4.16 (d, J=9.5 Hz, 1H),4.20–3.89 m, 4H), 3.21–3.05 (m, 2H), 2.81–2.51 (m, 2H), 2.47 (t, J=11.2Hz, 1H), 2.24 (d, J=14 Hz, 1H), 1.71 (dd, J=14, 6.4 Hz, 1H), 1.65 (m,2H), 1.47 (s, 9H). LCMS (M+H)=393.32.

Step C. A solution containing 37.7 mg (0.100 mmol) of the intermediateacid I in 1 mL of DMF was treated sequentially with BOP reagent (44.2mg, 0.100 mmol), the amine from step B (39.3 mg, 0.1 mmol), anddiisopropylethylamine (0.042 mL, 0.240 mmol). The reaction mixture wasstirred at ambient temperature for ten minutes. Evaporation of thesolvent and purification by reverse phase HPLC afforded the desiredketal that was used without further purification.

Step D. A solution containing 37 mg (0.05 mmol) of the ketal from step Cin 6 mL of 1:1 THF/3N HCl was heated at 55° C. for 2 h. The reaction wascooled, evaporated to ⅓ volume and purified by reverse phase HPLC toafford the desired compound as its TFA salt. ¹H NMR (CDCl₃ w/0.05%DMSO-d₆) δ 8.20 (s, 1H), 8.04 (s, 1H), 7.85 (m, 2H), 7.66 (m, 1H),7.44–7.15 (m, 10H), 5.30 (m, 1H), 4.25 (m, 2H), 4.11 (m, 1H), 3.77 (m,1H), 3.58 (m, 1H), 3.21 (m, 1H), 3.30 (s, 3H), 3.20 (m, 1H), 3.11–2.85(m, 4H), 2.80 (s, 3H), 1.61 (d, J=7 Hz, 3H). LCMS (M+1+H₂O)=625.32.

EXAMPLE 17

Step A. A solution containing 74.0 mg (0.236 mmol) of the acid fromintermediate VI in 2 mL of DMF was treated sequentially with BOP reagent(105 mg, 0.236 mmol), amine from Example 16, step B (93.0 mg, 0.236mmol), and diisopropylethylamine (0.099 mL, 0.566 mmol). The reactionmixture was stirred at ambient temperature for 15 minutes. Evaporationof the solvent and purification by reverse phase HPLC afforded the titlecompound that was hydrolyzed directly in the next step. LCMS(M+H)=588.32.

Step B. A solution containing 68.0 mg (0.10 mmol) of the ketal from stepA in 2 mL of 1:1 THF/3N HCl was heated at 55° C. for 2 h. The reactionwas cooled, evaporated and purified by reverse phase HPLC to afford thedesired compound as its TFA salt. ¹H NMR (CDCl₃ w/0.05% DMSO-d6) δ 7.99(s, 1H), 7.65 (m, 1H), 7.40–7.20 (m, 5H), 7.05 (s, 1H), 4.05 (m, 1H),3.90 (m, 2H), 3.22 (s, 3H), 2.94 (m, 4H), 2.80 (s, 3H), 2.45 (m, 1H),2.11 (m, 1H), 1.80 (m, 1H), 1.55 (m, 1H), 1.22 (m, 1H), 1.10 (bs, 3H),0.95 (m, 1H), 0.75 (m, 1H), 0.51 (m, 1H), 0.35 (m, 1H). LCMS(M+1)=544.29.

EXAMPLE 18

Example 18 was prepared in a manner similar to Example 16 steps A-Dusing carboxylic acid II. ¹H NMR (CD₃OD) δ 8.85 (d, 1H), 8.40 (d, 1H),7.99 (s, 2H), 7.66 (s, 1H), 7.44–7.00 (m, 9H), 5.20 (m, 1H), 4.25 (m,1H), 4.11 (m, 1H), 3.59 (m, 1H), 3.52 (m, 5H), 3.11 (m, 1H), 2.98 (s,3H), 2.80 (t, 1H), 2.31 (d, 1H), 2.08 (d, 1H), 1.85 (m, 2H), 1.65 (d,J=7.0 Hz, 3H). LCMS (M+1+H₂O) 643.26

EXAMPLE 19

A solution containing 10.0 mg (0.013 mmol) of Example 18 in 1 mL of MeOHwas treated with 3.7 mg (0.10 mmol) of NaBH₄. After stirring for 2 minthe mixture was chromatographed by reverse phase HPLC to afford thedesired alcohol. LCMS (M+1)=627.24.

EXAMPLE 20 R, S, S, R Diastereomer

Step A. To 102 mg (0.150 mmol) of the Boc-protected amine from Example12, step C dissolved in 5 mL CH₂Cl₂ was added Dess-Martin periodinane(0.191 g, 0.450 mmol) and the solution was stirred at ambienttemperature for 1 h. Purification by silica gel chromatography (80%EtOAc) gave the Boc-protected amino ketone. LCMS (M+H)=677.2.

Step B: To a 0° C. solution of 42 mg (0.062 mmol) of the Boc-protectedamino ketone in 2 mL ethanol was added sodium borohydride (4 mg, 0.093mmol). The reaction was stirred for 30 min and purified by reverse phaseHPLC to give a 4.3:1 mixture of alcohol diastereomer (S:R). The (S, S,R) Boc-protected amino alcohol was treated with 2.5 mL CH₂Cl₂:TFA (4:1)and stirred 30 min at ambient temperature. The reaction was evaporatedand purified by reverse phase HPLC to afford the desired compound as itsTFA salt. ¹H NMR (CD₃OD) δ 8.87 (d, J=6.5 Hz, 1H), 8.31 (d, J=8.9 Hz,1H), 8.07 (s, 1H), 8.00 (s, 1H), 7.86 (s, 1H), 7.41–7.15 (m, 10H), 5.24(q, J=6.3 Hz, 1H), 4.44 (m, 1H), 3.79 (d, J=9.0 Hz, 1H), 3.51 (m 1H),3.35 (s, 3H), 3.23 (t, J=7.1 Hz, 1H), 3.03 (d, J=7.7 Hz, 1H), 2.96 (s,3H), 2.31 (m, 1H), 1.99 (m, 2H), 1.71 (m, 1H), 1.58 (d, J=7.0 Hz, 3H).LCMS (M+H)=579.3.

EXAMPLE 21 R, S, R, S Diastereomer

Step A. To a stirred mixture of 1.1 g (6.1 mmol) of(S)-N-Boc-2-pyrrolidine (Donner, B. G. Tetrahedron Letters 1995, 36,1223–1226) and 0.70 g (6.08 mmol) N,N,N′,N′-tetramethylethylenediaminein 12 mL of ether at −78° C., 5.2 mL of 1.4M sec-butyllithium was addeddropwise. The reaction mixture was stirred at −78° C. for 40 min. Asolution of the N,N-dibenzyl-L-phenylalanal in 6 mL ether was then addedto the reaction mixture. The reaction was warmed to room temperatureover 16 h. The reaction was quenched with 100 mL of saturated bicarb andthe mixture was extracted with EtOAc (3×50 mL). The combined organicswere washed with brine (100 mL) before being dried over MgSO₄, filtered,and concentrated in vacuo. The residue was purified by silica gelchromatography (5%–60% EtOAc:Hex). The isolated product was thenpurified by reverse phase HPLC. Lyophilization provided thedibenzylamine. ¹H NMR (CD₃OD) δ 8.87 (s, 1H), 8.10 (s, 1H), 7.91 (s,1H), 7.77 (d, J=7.7 Hz, 1H), 7.65–7.14 (m, 13 H), 5.24 (m, 1H), 4.21 (m,1H), 3.97 (m, 1H), 3.21 (m, 1H), 2.78 (m, 2H), 2.28 (m, 1H), 2.26 (s,3H), 1.56 (d, J=7.1 Hz, 3H), 0.91 (m, 4H). LCMS (M+H)=515.4.

Step B. A solution containing 0.031 g (0.060 mmol) of the amine fromstep A in 1 mL MeOH was treated with a catalytic amount of Pearlman'scatalyst and stirred at room temperature under a hydrogen atmosphere for40 min. The reaction was filtered through plug of celite and the solventwas removed in vacuo. LCMS (M+H)=335.4.

Step C. A solution containing 22 mg (0.055 mmol) of the intermediateacid I in 3 mL of CH₂Cl₂ was treated sequentially with BOP reagent (24mg, 0.055 mmol), the (S, R, R) amine from step B (20 mg, 0.055 mmol),and diisopropylethylamine (0.03 mL, 0.167 mmol). The reaction mixturewas stirred at ambient temperature for 30 minutes. Evaporation of thesolvent and purification reverse phase HPLC to afford the amide. LCMS(M+H)=711.3.

Step D. A solution containing 9 mg (0.013 mmol) of the amide from step Cin 1 mL CH₂Cl₂ at 0° C. was treated with 1 mL TFA. The reaction wasstirred at 0° C. for 10 min. The solvents were removed in vacuo toafford the desired amino alcohol. LCMS (M+H)=611.3. ¹H NMR (CD₃OD) δ8.89 (d, J=7.5 Hz, 1H), 8.43 (d, J=8.8 Hz, 1H), 7.98 (m, 2H), 7.76 (m,1H), 7.42 (m, 2H), 7.23 (m, 5H), 5.23 (m, 1H), 4.20 (m, 1H), 4.03 (m,1H), 3.83 (m, 1H), 3.73 (m, 1H), 2.95 (s, 3H), 2.94 (s, 3H), 2.81 (m,2H), 2.21 (d, J=7.0 Hz, 3H), 1.57 (m, 4H), 1.39 (d, J=6.6 Hz, 3H).

EXAMPLE 22 [CIS (RS, SR)], S, R, R

Step A. A solution containing 0.41 g (1.6 mmol) of intermediate IV, 0.21g (1.6 mmol) of 1-bromo-2-butyne, and 0.22 g (1.6 mmol) K₂CO₃ in 15 mLof acetonitrile was heated at reflux for 3 h. The reaction mixture wascooled and diluted with 60 mL of H₂O. The mixture was extracted withEtOAc (3×60 mL). The combined organics were washed with brine (60 mL)before being dried (MgSO₄). The solvent was removed in vacuo andpurified by silica gel chromatography (20%–50% EtOAc:Hexanes) to affordthe alkylated aniline. LCMS (M+H)=311.2.

Step B. A solution containing 0.19 g (0.62 mmol) of aniline from step Ain 5 mL of MeOH was treated with a catalytic amount of Lindlar'scatalyst and stirred at room temperature under a hydrogen atmosphere for20 min. The reaction was filtered through plug of silica gel and thesolvent was removed in vacuo. Purification by reverse phase HPLCafforded the Z-alkenyl aniline. LCMS (M+)=313.2.

Step C. A solution containing 0.17 g (0.55 mmol) the alkenyl anilinefrom step B in 17 mL EtOAc at 0° C. was treated with 0.49 g (11 mmol) offreshly prepared diazomethane and a catalytic amount of palladium(II)acetate and stirred at 0° C. for 15 min. The reaction was filteredthrough a plug of silica gel. Evaporation of the solvent afforded themethyl cyclopropyl methyl aniline. LCMS (M+H)=327.2.

Step D. 0.17 g (0.52 mmol) of the methyl cyclopropyl methyl aniline fromstep C was dissolved in 6 mL MeOH:THF (1:1) and 0.78 mL (1.56 mmol) 2NNaOH was added. The reaction mixture was heated to 50° C. for 1 hour.The solution was cooled, acidified with 1N HCl (10 mL) and extractedwith EtOAc (3×30 mL). The combined organic extracts were dried overMgSO₄, filtered and concentrated in vacuo to afford the carboxylic acid.LCMS (M+H)=313.2.

Step E. A solution containing 0.071 mg (0.23 mmol) of the acid from stepD in 3 mL of CH₂Cl₂ was treated sequentially with BOP reagent (0.097 g,0.23 mmol), the amine from step B (0.091 g, 0.23 mmol), anddiisopropylethylamine (0.089 g, 0.69 mmol). The reaction mixture wasstirred at ambient temperature for 30 minutes. Evaporation of thesolvent and purification by reverse phase HPLC afforded the amide. LCMS(M+H)=687.3

Step F. A solution containing 0.038 g (0.055 mmol) of amide from step Ein 2 mL THF was treated with 1.7 mL 3N HCl. The reaction was stirred at55° C. for 1 h. The reaction was cooled and the solvents were removed invacuo. Purification by reverse phase HPLC gave the desired piperidinone.¹H NMR (CD₃OD) δ 7.23 (m, 4H), 7.15 (m, 1H), 7.04–6.89 (m, 3H), 4.09 (m,1H), 4.00 (m, 1H), 3.52–3.45 (m, 4H), 3.35 (s, 3H), 3.34 (s, 3H), 3.31(m, 2H), 3.25 (2H), 2.97 (m, 1H), 2.87 (m, 2H), 1.23 (m, 1H), 1.20–1.14(m 5H), 1.07 (m, 1). LCMS (M+H)=543.3.

EXAMPLE 23 CIS, S, R, R

Step A. A solution containing 2.36 g (8.21 mmol) of the acid fromintermediate I step C in 15 mL of CHCl₃ was treated sequentially withBOP reagent (3.63 g, 8.21 mmol), N,O-Dimethylhydroxylamine hydrochloride(0.96 g, 9.85 mmol), and diisopropylethylamine (6.43 mL, 36.9 mmol). Thereaction mixture was stirred at ambient temperature for 15 minutes.Evaporation of the solvent and purification by silica gel chromatography(5% MeOH/CHCl₃) afforded the desired N-methoxy-N-methyl amide. ¹H NMR(CDCl₃) δ 8.30–8.28 (m, 1 H), 8.11–8.08 (m, 1H), 7.94–7.92 (m, 1H), 3.94(s, 3H), 3.58 (s, 3H), 3.38 (s, 3H), 3.37 (s, 3H), 2.88 (s, 3H). LCMS(M+H)=331.0.

Step B. To a solution of the Weinreb amide from step A (1.30 g, 3.93mmol) in 10 mL of THF at −78° C. was added DIBAL-H (4.52 mL, 4.52 mmol)dropwise. The solution stirred for 1 hour at −78° C. and was quenchedwith MeOH (5 ml) and H₂O (5 mL). 2N HCl was added and the layers wereseparated. The aqueous phase was extracted with ether (3×25 mL) and thecombined organic extracts were washed with saturated NaHCO₃ and brine.The solvents were dried over MgSO₄, filtered and concentrated in vacuoto provide the crude aldehyde. ¹H NMR (CDCl₃) δ 10.0 (s, 1 H), 8.45–8.43(m, 1H), 8.29–8.27 (m, 1H), 8.10–8.08 (m, 1H), 3.98 (s, 3H), 3.40 (s,3H), 2.89 (s, 3H).

Step C. n-Butyllithium (0.15 mL of 1.6 M solution) was added to asuspension of cyclopropylmethyltriphenylphosphonium bromide (0.080 g,0.20 mmol) in a 2:1 mixture of THF and ether (3 mL) at 0° C. Afterstirring for 1 hour at ambient temperature the red solution was cooledto −78° C. and the aldehyde (0.05 g, 0.18 mmol) from step B in THF (1mL) was added. The resulting solution stirred for twelve hours beforethe solvents were removed in vacuo. The crude olefin was purified byreverse phase HPLC to afford a 1.65:1 ratio of Z:E isomers. Cis olefin:¹HNMR (CDCl₃) δ 8.01 (s, 1H), 7.83–7.81 (m, 1H), 7.72–7.70 (m, 1H), 6.32(d, J=11.5 Hz, 1H), 5.18 (t, J=10.8 Hz, 1H), 3.93 (s, 3H), 3.36 (s, 3H),2.86 (s, 3H), 1.88–1.80 (m, 1H), 0.92–0.87 (m, 2H), 0.53–0.49 (m, 2H).Trans olefin: ¹H NMR (CDCl₃) δ 7.90 (s, 1H), 7.76 (s, 1H), 7.52 (s, 1H),6.47 (d, J=15.7 Hz, 1H), 5.85 (m, 1H), 3.92 (s, 3H), 3.34 (s, 3H), 2.86(s, 3H), 1.57–1.50 (m, 1H), 0.87–0.84 (m, 2H), 0.55–0.53 (m, 2H) LCMS(M+H)=310.0.

Step D. 478 mg (1.54 mmol) of the phenethenyl cyclopropane from step Cwas dissolved in 6 mL MeOH:THF (1:1) and 1.15 mL (2.30 mmol) 2N NaOH wasadded. The reaction mixture was stirred for 1 hour. The solutionacidified with 1N HCl (10 mL) and extracted with EtOAc (3×30 mL). Thecombined organic extracts were dried over MgSO₄, filtered andconcentrated in vacuo to afford the carboxylic acid which was usedwithout further purification. LCMS (M+H)=296.1.

Step E. A solution containing 0.062 g (0.23 mmol) of the acid from stepD in 5 mL of CH₂Cl₂ was treated sequentially with BOP reagent (0.093 g,0.21 mmol), the amine from Example 16, step B (0.10 g, 0.25 mmol), anddiisopropylethylamine (0.16 g, 0.95 mmol). The reaction mixture wasstirred at ambient temperature for 30 minutes. Evaporation of thesolvent and purification by reverse phase HPLC afforded the amide. LCMS(M+1)=670.2

Step F. A solution containing 0.06 g (0.089 mmol) of amide from step Ein 1.5 mL THF was treated with 1.5 mL 3N HCl. The reaction was stirredat 55° C. for 1 h. The reaction was cooled and the solvents were removedin vacuo. Purification by reverse phase HPLC gave the desiredpiperidinone. ¹H NMR (CD₃OD) δ 7.59–7.47 (m, 2H), 7.43–7.39 (m, 2H),7.33–7.14 (m, 4H), 6.02 (d, J=11.3 Hz, 1H), 5.05 (t, 1H), 4.38–4.22 (m,1H), 4.06–3.93 (m, 1H), 3.82–3.40 (m, 1H), 3.05–2.82 (m, 3H), 2.58 (m,2H), 1.75–1.63 (m, 3H), 1.26–0.94 (m, 6H), 0.58–0.43 (m, 2H). LCMS(M+H)=544.0

While the invention has been described and illustrated with reference tocertain particular embodiments thereof, those skilled in the art willappreciate that various adaptations, changes, modifications,substitutions, deletions, or additions of procedures and protocols maybe made without departing from the spirit and scope of the invention. Itis intended, therefore, that the invention be defined by the scope ofthe claims that follow and that such claims be interpreted as broadly asis reasonable.

1. A compound of the formula I:

wherein; R¹ is

R² is selected from the group consisting of: (1) R⁴—S(O)_(m)—NR⁵—, (2)R⁴—S(O)_(m)—, (3) R⁴NHCO—, (4) R⁴CONH—, (5) R⁴R⁵N—, (6) nitrile, (7)NC—C₁₋₆alkyl—, (8) halogen,

R³ is selected from the group consisting of:

R⁴ is selected from the group consisting of: (1) hydrogen, (2)C₁₋₆alkyl, (3) phenyl, and (4) benzyl; R⁵ is independently selected fromthe group consisting of: (1) hydrogen; (2) C₁₋₆alkyl, (3) phenyl, (4)benzyl, and R^(6a), R^(6b), and R^(6c) are independently selected fromthe group consisting of: (1) hydrogen, (2) halogen, (3) —OR⁵, (4) —SR⁵,and (5) C₁₋₆alkyl; R⁷ is selected from the group consisting of —C═C—, O,S, and NH; Z is selected from the group consisting of CO, CH—OH, and

R^(8a) and R^(8b) are independently selected from the group consistingof: (1) nitrile (2) hydrogen, (3) halogen, (4) —OR⁵, (5) —SR⁵, (6)C₁₋₆alkyl, (7) —CO₂R⁵, and (8) tetrazolyl; X¹ is hydrogen and X² ishydroxyl; n is independently 1, 2, 3, or 4; m is independently 0, 1, or2; and pharmaceutically acceptable salts thereof.
 2. The compound ofclaim 1 wherein: R⁵ is hydrogen or methyl;  and pharmaceuticallyacceptable salts thereof.
 3. The compound of claim 1 wherein R² is;R⁴—S(O)₂—NR⁵—  and wherein R⁴ is selected from the group consisting of:(1) hydrogen, (2) C₁₋₆alkyl, (3) phenyl, and (4) benzyl; R⁵ is selectedfrom the group consisting of: (1) C₁₋₆alkyl, (2) phenyl, (3) benzyl, and(4) hydrogen; and pharmaceutically acceptable salts thereof.
 4. Thecompound of claim 1 wherein R³ is:

and wherein: R⁴ is methyl; R^(6a) is H or F; R^(6b) and R^(6c) arehydrogen; and pharmaceutically acceptable salts thereof.
 5. The compoundof claim 1 wherein R³ is:

wherein: R⁵ is methyl; R⁷ is O or NH; and pharmaceutically acceptablesalts thereof.
 6. The compound of claim 1 which is selected from thegroup consisting of:

and pharmaceutically acceptable salts thereof.
 7. A compound of claim 1in substantially diastereomerically pure form.
 8. A substantiallydiastereomerically pure compound of claim 1 in substantiallyenantiomerically pure form.
 9. A pharmaceutical composition comprising atherapeutically effective amount of a compound of claim 1 and apharmaceutically acceptable carrier.
 10. A method for treatingAlzheimer's disease in a patient comprising the administration to thepatient of a therapeutically effective amount of a compound of claim 1.